Marasmius alliaceus (Jacq.) Fr. 1838. Epicrisis 383.

Basidiomata marasmielloid, marasmioid or collybioid, either diminutive or moderately sized, reviving or not. Pileus 3–15 or 20–50 mm broad, at first strongly convex becoming campanulate to convex to applanate with decurved margin, off-white to pigmented in brownish, reddish brown to yellowish brown with disc always somewhat darker than limb or margin, smooth or suede-like, sometimes weakly hygrophanous; pileus margin entire to shallowly sulcate-striate; trama thin to fairly thick. Pileus trama pliant. Lamellae ridge-like to well-developed, thin or thick, distant to moderately crowded, free, adnexed to adnate, often attached to a thin, weak pseudocollarium best demonstrated in dried basidiomata. Stipe 8–60 mm long, central, insititious to not so, usually with distinct basal mycelium, hollow or lightly stuffed but not solid, glabrous, pubescent or furfuraceous, paler upward, downward dull greyish tan to reddish brown or dark brown or nearly black. Odor negligible or (usually) very distinct, like onion or garlic.

Saprophytic on decaying deciduous leaves, buried rotting wood, bark (including bark of living, standing trees) and in one species on mixed conifer detritus; distribution in Europe (My. alliaceus, My. scorodonius, My. kallioneus, My. prasiosmus, My. subalpinus), trans-Mediterranean (My. virgultorum) western and eastern North America (My. applanatipes, My. olidus, My. salalis, My. scorodonius and f. diminutivus), Asia (My. yunnanensis) and Antipodes (My. curraniae, My. cinnamomeus).

Pileipellis a hymeniform layer of inflated hyphal termini sometimes with scattered broom cell-like pileocystidia especially at pileus margin; elements clamped, stalked, subglobose, obpyriform, deeply lobed, occasionally strongly pigmented, firm-to thick-walled, rarely with a few knobs or finger-like apical projections. Pleurocystidia present, from poorly differentiated to narrowly or broadly fusiform; contents homogeneous, sometimes vaguely partitioned. Basidia clavate, sometimes subcapitulate, (2-)4-sterigmate, often long, clamped; contents heterogeneous, appearing oily (PhC). Basidiospores either narrowly clavate (Q^m = >3), or ellipsoid to broadly ellipsoid (Q^m = <2.5), marasmioid, subamygdaliform or broadly ellipsoid. Cheilocystidia present, from undifferentiated from basidioles, cylindrical, clavate, subampulliform, lageniform, sometimes arbuscular with digitate outgrowths. Caulocystidia present or absent, often gathered into floccose clusters or synnematoid projections. Rhizomorphs unreported; telepods very rarely present on extra-European taxa only.

Mycetinis taxonomic outline:

1. Mycetinis alliaceus (Jacq.: Fr.) Earle. 1909. Bull. N.Y. Bot. Gard. 5: 414.

2. Mycetinis applanatipes (Desjardin) A.W. Wilson & Desjardin. 2005. Mycologia 97: 677.

3. Mycetinis cinnamomeus (Cleland) R.H. Petersen & Desjardin. (below)

4. Mycetinis copelandii (Desjardin) A.W. Wilson & Desjardin. 2005. Mycologia 97: 677.

5. Mycetinis curraniae (G. Stev.) J. A. Cooper & P. Leonard. 2012. Index Fungorum 3: no. 550026.

6. Mycetinis kallioneus (Huhtinen) Antonín & Noordel. 2008. Czech Mycol. 60: 26.

7. Mycetinis olidus (Gilliam) R.H. Petersen (below)

8. Mycetinis opacus (Berk. & M.A. Curtis) A.W. Wilson & Desjardin. 2005. Mycologia 97: 677.

9. Mycetinis prasiosmus (Fr.: Fr.) R.H. Petersen (below)

= Mycetinis querceus (Britzelm.) ss. Antonín & Noordel. 2008. Czech Mycol. 60: 26.

10. Mycetinis salalis (Desjardin) Redhead. 2012. Index Fungorum 8: 1.

11. Mycetinis scorodonius (Fr.: Fr.) A.W. Wilson & Desjardin. 2005. Mycologia 97: 678.

11A. Mycetinis scorodonius f. diminutivus R.H. Petersen, K. Dyson & J. Ammirati (below)

12. Mycetinis subalpinus (P.-A. Moreau) P.-A.Moreau & R.H. Petersen (below)

13. Mycetinis virgultorum (Malençon & Bertault) R.H. Petersen (below)

14. Mycetinis yunnanensis R.H. Petersen (below)

(neotype, design. Antonín and Noordeloos 1993: Austria, Steiermark, Wildalpen [N47°39'52", E14°59'11"], Lurghöhe, 12.VII.1981, J. Schreurs 578 (L)

1) Basidiomata of moderate size (pileus -40 mm broad; stipe 40–85 × 3–5 mm); 2) cheilocystidia short-stalked, digitate to cigar-shaped; 3) stipe brown-black, lightly vestured upward, often pruinose basally; 4) basidia with heterogeneous (multiguttulate) contents; 5) pileipellis elements subglobose to obpyriform, firm-walled; 6) stipe often pseudorhizal, usually associated with Fagus sylvatica; 7) dried basidiomata retaining garlic taste; 8) basidiospores broadly ovate to amygdaliform, firm-walled; 9) spore contents heterogeneous, with 1-several inclusions.

Basidiomata (Fig. 3) of moderate size. Pileus 5–45 mm broad, conical when young becoming truncate-conical to more or less plane with downturned margin, usually deeply sulcate-striate almost to disc, smooth (matt, not glabrous), wrinkled (radially and circumferential) when dried, more or less unicolorous, light brown 6D4-6 (near “sayal brown” 6C3 to “tawny olive” 5C5), often with violaceous tint (“tilleul buff” 7B2 to “vinaceous buff” 9B2), reluctantly bruising in spots to “sorghum brown” 8D5; margin delicately scalloped, sometimes abruptly off-white. Lamellae adnate to adnexed, close to crowded, thin, -2 mm broad, entire (not serrulate), total lamellae 75–135, through lamellae 18-24, white to slightly yellowish 5A-B2 to (dried) “ochraceous buff” 5A5, “light vinaceous fawn” 10B2, bruising to “livid brown” 10D4 or “russet” 7D6; lamellulae in 3-4 ranks. Stipe 40–85 × 3–5 mm, erect, terete or somewhat compressed, especially apically, straight, not insititious, upward often brown 6E4-7 to deep maroon (“Hay’s russet” 8D7, “Kaiser brown” 7E8), downward darkest brown “clove brown” 6F3, “bone brown” 7F8 to “aniline black” 12F3, lightly vestured above, more heavily so near base (and there with mouse gray to “old gold” 3C6 vesture); base occasionally appearing short-pseudorhizal, disappearing in humus, perhaps reaching buried wood, soil often composed of insect castings. Rhizomorphs apparently within substrate (not extrinsically visible), -24 × 0.8–1 mm diam, now copper-brown, curly, occasionally branched; branches usually small, peg-like. Odor strong of garlic; taste distinct of garlic, sometimes also acrid.

Figure 3. 

Mycetinis alliaceus. Habit photo. Standard bar = 10 mm. Courtesy Pilzgalerie.

Antonín & Noordeloos (2010) describe ecology as “Gregarious on decaying stems and twigs of Fagus sylvestris, rarely also on the leaves, also recorded from Carpinus … and coniferous needles …” It can be concluded that the preferred substrate is woody. Known from most of the European Fagus distributional area; Russian Caucasus, western Russia, continental Europe, British Isles and Scandinavia; to this time, appearing absent from North America. Late summer, autumn.

Pileipellis a more or less hymeniform layer of inflated cells (Figs 4, 5) not apparently involved in a slime matrix; cells 30–45(-60) × 12–23 µm (at widest point), stalked (stalk 7–40 × 4–6 µm), conspicuously clamped, firm-walled; inflated portion obpyriform to subglobose, firm-walled, hyaline, smooth to minutely roughened, occasionally misshapen, especially at pileus margin, and/or with apical diverticula ranging from short lobes to subcoralloid structures; contents homogeneous. Pileocystidia apparently absent. Pileus tramal hyphae filamentous, 4–8 µm diam, firm-walled, loosely interwoven, conspicuously clamped, not involved in a slime matrix or gelatinized walls. Lamellar trama loosely interwoven; hyphae 4–25 µm diam, firm-walled, conspicuously clamped, hyaline. Pleurocystidia (Fig. 6A–D) 36–44 × 9–12 µm, fusiform, usually with submammilate apex, thin-walled, conspicuously clamped; contents homogeneous. Basidioles (Fig. 6E–H) clavate; basidia 39–43(-54) × 10–14 µm, clavate, 4-sterigmate, clamped; contents granular to granulo-guttulate. Basidiospores (Fig. 7) (7.5-)9.5–11.5 × (4.5-)5.5–6(-9) µm (Q = 1.06–2.20; Q^m = 1.51; L^m = 9.86 µm), subglobose, ovate to subtly amygdaliform, firm-walled, hyaline, inamyloid; contents heterogeneous with dark inclusions (PhC); spores copious on lamellar surface; empty spores not collapsing. Cheilocystidia (Figs 8, 9) 45–72 × 7–20 µm (at widest point), stalked (stalk 6–12 × 3–5 µm, obscurely clamped), cylindrical, cigar-shaped, occasionally fusiform or sublageniform, bluntly rounded apically, sometimes producing lobate or digitate outgrowths (perhaps when revived in nature or confined), firm-walled, hyaline; contents homogeneous. Stipe medullary hyphae strictly parallel, 4–7.5 µm diam, thin-walled, hyaline, without slime matrix, obscurely clamped. Stipe cortical hyphae coherent but without discernable slime, 4–8 µm diam, thick-walled (wall -1.0 µm thick), obscurely clamped, pigmented yellow-brown, producing caulocystidia as side branches or hyphal termini. Caulocystidia (Fig. 10) from upper stipe scattered, 10–75 × 7–11 µm, digitate, cylindrical, often with constrictions, arising as side branches of stipe surface hyphae or as surface hyphal termini, arranged perpendicular to stipe surface or repent against it, thick-walled (wall -1.5 µm thick), hyaline, smooth. Caulocystidia from stipe base identical, thickly gregarious, 10–110 × 7–13 µm, perpendicular to stipe surface as a turf.

Figure 4. 

Mycetinis alliaceus. Pileipellis elements. Standard bars = 10 µm. TFB 11451 (TENN-F-59312).

Figure 5. 

Mycetinis alliaceus. Abnormal pilepellis elements from pileus margin. Standard bars = 10 µm. TFB 11451 (TENN-F-59312)

Figure 6. 

Mycetinis alliaceus. A–D Pleurocystidia. Note homogeneous contents. E–H Basidia. Note heterogeneous contents. Standard bars = 10 µm. TFB 11451 (TENN-F-59312).

Figure 7. 

Mycetinis alliaceus. Basidiospores. Standard bar = 5 µm. TFB 11451 (TENN-F-59312).

Antonín and Noordeloos (2010): “Lamellae distant, L = 14–24 (27), l = 1–3, free or narrowly adnexed with decurrent tooth, sometimes attached to a pseudocollarium, rather broad, whitish or grayish, often with brown-red stains when old, with entire or pruinose, sometimes serrulate, concolorous or slightly darker edge.” Their photo, however, has a suggestion of many more lamellae. As the description above reports, total lamellae and through lamellae statistics do not agree.

Pleurocystidia are apparently produced by selected basidiomata and not by others. The specimen from Austria produced large numbers of differentiated pleurocystidia, but TFB 4731 does not exhibit mature pleurocystidia. Immature pleurocystidia may be present and common, but they are indistinguishable from basidioles. When basidia are nearing maturity they begin to exhibit the heterogeneous contents typical of the species.

TENN-F-55620 was used by Vasiliauskas et al. (2005) as a representative to AFTOL (GenBank AY781252).

Unlike My. scorodonius, which exhibits common differentiated pileocystidia (modified broom cell-like termini) at the pileus margin, the pileipellis of My. alliaceus extends from pileus margin to center with no differentiation of a second element. The most differentiation observed has been some adventitious apical growths from otherwise typical inflated shapes.

Austria, Lower Austria, Waldviertel Forest, vic Dobrasperre, N48°38.477', E15°48.338', 24.IX.2001, coll. RHP, TFB 11451 (TENN59312). France, Rhone-Alpes, Dpt. Isére, Col de Granier, 11.IX.2001, coll. RHP, TFB 11352 (TENN59237). Germany, Thuringia, vic. Muchinsojra, Helbeta, N51°24.131', E10°36.052', 30.VIII.2012, coll RHP, TFB 14161 (TENN67911). Russia, Krasnodar Region, vic. Plukh, slopes of Krasnaya Polya, N43°38.677', E40°26.668', 20.IX.1996, coll RHP, TFB 8960 (TENN55620). Sweden, Halland Co., vic Töto Parish, N56°53'50", E12°48'11.5", coll unknown, TFB 4731 (TENN50328); Västergotland, Partille Parish, Jonsered (15 Km east of Gothenburg), N57°44'50", E12°10'25", 28.IX.1991, coll SA Gordon, RHP, Robert Daun, TFB 4737 (TENN50334).

Figure 8. 

Mycetinis alliaceus. Cheilocystidia. Standard bars = 10 µm. TFB 11451. (TENN-F-59312).

Figure 9. 

Mycetinis alliaceus. Cheilocystidia, showing adventitious apical outgrowths. Standard bars = 10 µm. TFB 4737 (TENN-F-50334).

Figure 10. 

Mycetinis alliaceus. Caulocystidia from upper stipe. A Repent caulocystidium against stipe surface B–DCaulocystidia perpendicular to stipe surface E General view of lower stipe surface. Standard bars = 10 µm. TFB 11451 (TENN-F-59312).

1) Basidiomata of small to moderate size (pileus 10–18 mm broad; stipe 30–40 × 1.5–3 mm); 2) pileus disc reddish brown, margin greyish orange; 3) strong alliaceous odor and taste; 4) entirely vestured, bicolored stipe, typically compressed; 5) cheilocystidia poorly differentiated, clavate to occasionally bifid; 6) spores broadly ellipsoid to subamygdaliform.

Basidiomata (Fig. 11) of small to moderate size. Pileus 10-18 mm broad, when young strongly convex, in age becoming shallowly convex to plane, rarely shallowly everted, dry, dull, glabrous, subtly subhygrophanous; disc dark reddish brown (8F4-8) overall when young, in age disc remaining dark brown (7F4-8), brown (7E4-6) or light brown (7D5-7); margin incurved when young, becoming decurved to uplifted, entire, even, smooth to minutely rugulose-striate to short sulcate, fading to brownish gray (6C3), greyish orange (5-6B2-4) or pinkish buff. Pilus trama up to 1 mm thick, soft, brown to brownish grey. Lamellae adnate to adnexed, often attached to an adherent pseudocollarium (best seen in dried material), subdistant to distant, thick, total lamellae 40–50, through lamellae 13-16, medium broad to broad (1–2.5 mm broad), rarely anastomosing and intervenose, (fresh) at first buff or orange white (5A2) to greyish orange (5-6B3), mellowing with age, often becoming brown (7E4-5), (dried) “cartridge buff” 30A2, “cream buff” 4A4, “chamois” 4B4 ; edge even, entire, wavy in age, paler than faces when dried; lamellulae in 1-2 series. Stipe 30–40 × 1.5–3(-4) mm, when young terete and equal, in age becoming compressed and often cleft, typically tapered downward, cartilaginous, hollow, non-insititious, upward pubescent, velutinous in midsection, at base subtomentose to tomentose, with tomentum intricately tangling with substrate, when young, upward buff to orange white (5A2), in age brownish orange (8E4-7), in midsection brownish grey (6C3), downward brown (6-7E5-7) to reddish brown (8E4-8), base dark brown (7B4-8) to dark reddish brown (8F4-8); medulla concolorous with stipe surface. Rhizomorphs and sterile stipes not reported. Odor and taste strongly alliaceous.

Figure 11. 

Mycetinis applanatipes. Basidiomata. Standard bars = 10 mm. DED 2330 (SFSU). Courtesy Dennis Desjardin.

Scattered, densely gregarious to subcespitose in duff under mixed conifers (mainly species of Pseudotsuga, Abies concolor and Pinus contorta) at elevation above 6000 feet in Sierra Nevada and Cascade Range in California; uncommon; Oct-Nov.

Pileipellis from near pileus margin a roughly hymeniform layer -50 µm thick composed of several elements: 1) pileal hairs (Fig. 11A–D) 30–90 × 4–6.5 µm, arising as side branches of repent subpellis hyphae, very delicately roughened, occasionally internally clamped, sometimes undulate or shallowly lobate, thin-walled; contents densely homogeneous to heterogeneous; 2) inflated hyphal termini (Figs 11E–H, 12, 14A–B) 24–50(-65) × 5–14 µm, stalked, ranging from ventricose-rostrate, subglobose to elongate or complex-lobate, firm-walled, conspicuously clamped, firm-walled (wall -0.6 µm thick, hyaline; 3) similar scattered elements with dense contents, usually branched or lobate; and 4) scattered thick-walled lobate elements (Fig. 14C, D) with densely, strongly pigmented contents. Pileus trama loosely interwoven, composed of hyphae of three types: 1) filamentous, 3–8(-15) µm diam, firm-walled, conspicuously clamped, often swollen at branch-points; 2) filamentous, 3–8 µm diam, firm-walled, delicately to coarsely encrusted (Fig. 14G, H), with crust material in scabs or spiculate deposits; and 3) lobate, free-form, firm- to thick-walled (wall -0.7 µm thick, hyaline) in a loose textura intricata (Fig. 14F). Lamellar trama subparallel to interwoven, composed of smooth, hyaline, inamyloid, cylindric hyphae 3–4 µm broad with walls up to 0.6 µm thick; conspicuously clamped. Pleurocystidia (Fig. 15) common (but not abundant), (35-) 40–75 × 2.5–8 µm, cylindrical to narrowly clavate or occasionally subampulliform-rostrate, conspicuously clamped; contents more or less homogeneous. Basidioles subclavate, not capitulate, conspicuously clamped; contents delicately multiguttulate, increasingly so with maturity; basidia (Fig. 17A–D) (35-)40–48(-59) × 7–9 µm, clavate, often subcapitulate, obscurely clamped, hyaline, with granular or globular refractive contents, (1-, 2-)4-sterigmate, with sterigmata up to 6 µm long; contents coarsely multiguttulate, refringent (PhC); some collections predominantly two-spored and these with consistently larger spores. Effete basidia not collapsing after evacuation, remaining more or less intact in hymenium (“husking”). Basidiospores (Fig. 16) (7.5-)8.7–10.2(-12) × 4.8–6(-6.6) µm, µm (Q = 1.18–1.92; Q^m = 1.57; L^m = 9.2 µm), pip-shaped, broadly ellipsoid to amygdaliform, hyaline, smooth, inamyloid, white in deposit. Cheilocystidia (Fig. 17E–H) scattered, uncommon, 33–48(-56) × 6–10 µm, clavate to cylindric-subcapitulate or bifid with two lobes typically unequal in length and occasionally with a few short lateral knobs, with thin, hyaline, inamyloid walls, obscurely clamped, easily disarticulated; contents delicately to coarsely multiguttulate. Stipe medullary hyphae parallel, 2.5–12 µm diam, thin-walled (wall hyaline to pale yellowish brown, inamyloid, walls up to 0.6 µm thick), conspicuously clamped; stipe cortical hyphae 2–4.5 µm diam, strictly parallel, firm-walled, hardly pigmented, producing caulocystidia as side branches and/or hyphal termini. Caulocystidia of upper stipe surface (Fig. 18) (26-)40–100 × 9–15 µm, arising as hyphal termini or side branches, broadly cylindrical, undulate, apically bluntly rounded, hyaline, perpendicular to stipe surface, narrowed somewhat at origin, firm-walled, in clusters or scabs so appearing as delicate floccose scales; contents more or less homogeneous, non-refringent (PhC); caulocystidia of basal tomentum with dark brown, evenly pigmented walls up to 1.2 µm thick.

Figure 12. 

Mycetinis applanatipes. Pileipellis structures. A–D Pileal hairs E–H Inflated hyphal termini. Standard bars = 10 µm. DED 6628 (SFSU-F- 024637).

Figure 13. 

Mycetinis applanatipes. Pileipellis structures. A–D Lobate hyphal termini E–H Structures with dense protoplasm, usually lobate or branched. Standard bars = 10 µm. DED 6628 (SFSU-F- 024637).

Figure 14. 

Mycetinis applanatipes. Pileipellis and subpellis structures. A, B, E Complex lobate hyphal termini C, D Thick-walled, strongly pigmented elements F Loosely complex pileus tramal hyphae G Encrusted hyphae H Detail showing spiculate crust material. Standard bars = 10 µm. DED 6628 (SFSU-F- 024637).

Figure 15. 

Mycetinis applanatipes. Pleurocystidia. Standard bars = 10 µm. DED 6628 (SFSU-F- 024637).

Figure 16. 

Mycetinis applanatipes. Basidiospores. Standard bars = 5 µm. DED 6628 (SFSU-F- 024637).

Figure 17. 

Mycetinis applanatipes. Basidia and cheilocystidial structures. A Monosterigmatal basidium B, C 2-sterigmate basidia D 4-sterigmate basidium E–H Cheilocystidial structures. Standard bars = 10 µm. DED 6628 (SFSU-F- 024637).

Figure 18. 

Mycetinis applanatipes. Caulocystidia from stipe apex. A Caulocystidium as hyphal terminus B Caulocystidium as side branch C–E Individual caulocystidia. Standard bars = 10 µm. DED 6628 (SFSU-F- 024637).

Numbers of through lamellae is somewhat low for Mycetinis, but the single rank of rudimentary lamellulae is consistent with other species. Stipe length/ pileus diameter ratio is rather low (i.e. stipes are somewhat short, but robust for their length), with several other taxa rather gracile. Habitat on mixed conifer needles is also uncommon, with several other taxa on deciduous leaves or rotten buried wood.

Unexpectedly, the ITS sequence of DED 6628 is close to that of M. prasiosmus from Europe (minimum percent difference = 2.19%). Numerous non-molecular characters differ, however, include basidiomatal size and stature, ecological niche and distribution.

United States, California, Placer Co., Yuba Gap, Hwy 80, N39°18'55.66", W120°37'08.15", 6.XI.1983, coll. & det. DE Desjardin (as Marasmius applanatipes), DED 2469 (SFSU-F- 024633) California, Sierras Co., Chapman Creek Campground, off Hwy 49, N39°37'49.85", W120°32'37.80, 4.X.1997, coll. Desjardin & Perry, det. DE Desjardin, DED 6628 (SFSU-F-024637); Sierra County, Yuba Pass, N35°19'23.65", W120°35'56.92", 8.X.1983, coll. & det. DE Desjardin, DED 2330 (as Marasmius applanatipes)(SFSU-F- 000646; holotype p.p.); Siskiyou Co., vic. Callahan [N40°18'45", W122°48'05"], Carter Meadow, 20 mi W of Weed, 1.X.1983, coll. & det. DE Desjardin, DED 2236 (SFSU-F- 024634).

[lectotype, design. (Grgurinovic 1997)]: Australia, South Australia, Belair Nat. Park, S35°00'44.79", E138°38'54.54", 7.VII.1934, coll. J.B. Cleland, Cleland no 10002 (AD 10986).

1) Basidiomata diminutive (pileus 4–12 mm broad; stipe 6–12(-25) × 0.6–1 mm); 2) pileipellis hymeniform, of firm- to thick-walled inflated hyphal termini; 3) basidiospores broadly ellipsoid to subamygdaliform; 4) caulocystidia absent; 5) reported lack of odor; 6) habitat on bark of living eucalypts; 7) fruiting in late autumn to winter; South Australia.

The following description is a combination of the protolog, Grgurinovic’s (1997) treatment and Desjardin’s notes (pers. comm.) on three Cleland specimens.

Basidiomata diminutive. Pileus -12 mm broad, at first convex with inturned margin, then nearly plane, “light pinkish cinnamon” 7A2, “pinkish buff” 6A3, “light vinaceous cinnamon” 7A3 or “light ochraceous salmon” 6A4, darker over the disc; surface dull and slightly villose or minutely frosted, subrugose, sometimes shallowly substriate at margin. Lamellae adnate, then seceding, moderately close to somewhat distant, presence or absence of pseudocollarium unreported, slightly ventricose, cream-colored or white; edge sometimes appearing delicately serrulate. Stipe -12(-25) × 0.6–1mm, subinsititious, slender, slightly velutinous or smooth, near “Hessian brown” 9E7 or “Vandyke brown” 7E6, paler above, downward darker, sometimes nearly black below. Odor reported as negligible; taste not recorded.

Gregarious on thick bark at the bases of living eucalypts; South Australia; May-July.

Pileipellis (Fig. 19A) more or less a hymeniform layer of inflated hyphal termini not involved in a slime matrix; cells clavate, obpyriform, sphaeropedunculate, molar-shaped to coarsely lobed, firm- to thick-walled (wall 0.5–2.5 µm thick), occasionally with irregular short apical diverticula, hyaline to golden brown; diverticula 15.2–29.6 × 7.8–13.6 µm. Subpellis hyphae cylindrical, not encrusted, conspicuously clamped. Pleurocystidia not reported but probably narrowly fusiform as in other taxa of the genus. Basidioles clavate; basidia 24.0–32.0 × 6.2–10.0 µm, clavate, sometimes versiform in midsection, 2–4-sterigmate; sterigmata -6.0 µm long. Basidiospores (Fig. 19B) 7.2–10.2 (-12) × 3.4–5.1(-6.2) µm [Q^m = 2.0; L^m = 8.4 µm], ellipsoid, subovate to subamygdaliform, smooth, thin-walled, inamyloid. Lamellar edge fertile; cheilocystidia (Fig. 19) scattered, (11.2-)18.4–33.6 × 5.6–16 µm, broadly clavate, hyaline, firm-walled, clamped; main body 13–20 × 7–9 µm, hyaline, diverticulate; diverticula 3–8 × 1.5–3 µm. Stipe cortical hyphae 3–6.5 µm diam, parallel, cylindrical, thick-walled, orange brown, with granular to annular encrustation. Caulocystidia absent.

Figure 19. 

Mycetinis cinnamomeus. A Pileipellis elements B Basidiospores C Cheilocystidia. Standard bars = 10 µm. From Desjardin notes on AD 31401.

Desjardin and Horak (1997) drew attention to similarities between M. curraniae Stevenson from New Zealand and M. cinnamomeus from South Australia. Since then, M. curraniae has been recombined into Mycetinis (Cooper and Leonard 2012) and molecular data have shown its placement with other taxa of Mycetinis. Unfortunately, molecular data for M. cinnamomeus have not yet been produced, but Cleland’s report of “odour none” notwithstanding, all other characters point to its inclusion with other taxa of Mycetinis, especially those with diminutive basidiomata (i.e. My. olidus, M. yunnanensis). The proposed nomenclatural new combination is intended to bring this additional taxon into Mycetinis.

Grgurinovic (1997) translated Clelend’s (1934) Latin description into English, adding observations on microstructures.

As is common for some other taxa of Mycetinis, M. cinnamomeus was considered by Grgurinovic (1997) as belonging in Marasmius sect. Epiphylli, and Desjardin and Horak (1997) indicated section Chordales (by implication of similarity to M. curraniae). Other than literature cited here, little is known about Cleland’s taxon. It seems to have eluded collection since Cleland’s finds. The diminutive basidiomata seem similar to those of M. virgultorum, M. olidus, M. curraniae and M. yunnanensis.

Cleland (1934) listed four locations as distribution of M. cinnamomeus: Belair National Park (S35°00'44.79", E138°38'54.54"), Willunga Hill (S35°18'44", E138°34'35"), Mt. Lofty (S34°58'25.65", E138°42'32.25") and Inman Valley (S35°28'00.30", E138°27'19.06"). Both Grgurinovic (1997) and Desjardin (unpubl.) examined AD 10986, while Desjardin examined two additional specimens.

Spore dimensions by Cleland (1934) and Grgurinovic (1997) are somewhat smaller than those by Desjardin (in litt. and included above).

Specimens examined (by DED): Australia, South Australia, Willunga Hill, 31.V.?, coll. J.B. Cleland, Cleland no. 10037 (AD 31401); South Australia, Belair Nat. Park, 7.VII.1934, coll. J.B. Cleland, Cleland no 10002 (AD 10986, lectotype); South Australia, National Park, 28.V.1927, coll. J.B. Cleland, Cleland no. 392 (AD 31402).

California, San Mateo Co., Woodside, N37°25'49", W122°15'12", 7.XII.1902, coll. EB Copeland, Copeland 14 (herb. Peck, NYS).

1) Basidiomata small but robust; 2) fruiting preference on dead Lithocarpus leaves; 3) pileipellis constructed of broadly clavate to obpyriform cells and complex free-form textura intricata hyphal termini; 4) cheilocystidia basically clavate but often with a few prominent apical lobate outgrowths; 5) basidiospores (9-)10.5–12(-15) × 3–4(4.5) µm, with heterogeneous contents; 6) pleurocystidia presumptive, cylindrical to narrowly fusiform; 7) stipe entirely vestured, furry at base; 8) caulocystidia of two width classes; 9) distribution in northern California.

Basidiomata (Fig. 20) small but robust. Pileus (4-)8–24 mm broad, convex when young, becoming shallowly convex, plane to shallowly everted in age, smooth, dry to moist, subglabrous, usually entirely fading in color in age; disc “Verona brown” 6E5, “bone brown” 7F8, “Sudan brown” 6E7. “Argus brown” 6E8, “auburn” 7E5, “Vandyke brown” 7E6, “burnt umber” 7E7, to “Kaiser brown” (6-7E5-8) when young, fading to near “buffy brown” 6D4-5, near “buckthorn brown” 5C5-7 or near “drab” 6C4 in age; margin at first incurved, entire, even, “buffy brown” 6D4-5, “Rood’s brown” 6-7D4-5, soon becoming decurved, shallowly translucent-striate, in age rugulose-striate, near “tilleul buff” 5B4 or “pale cinnamon pink” 5A2–3; trama 0.5–1 mm thick, near “sayal brown” 6C3. Lamellae adnate to adnexed, close to subdistant (13–16 reach the stipe), thickish, occasionally pseudocollariate, subventricose, shallow (1–1.5 mm width), rarely forked or intervenose, at first “pale cinnamon pink” 5A2, becoming near “tilleul buff” 6B3 in age, often spotted “Rood’s brown” 7D5-6 to “vinaceous russet”8D4, developing necropigment of “light ochraceous buff” 5A4; edges even and entire when young, concolorous with or slightly paler than the faces; lamellulae in 1–2 series. Stipe (15-)25–65(75) × 1–4 mm, terete when young, often becoming compressed in age, equal or tapered somewhat downward, non-insititious, occasionally somewhat rooting, tough, pliant, hollow to stuffed, vestured overall, pruinose to pubescent upward and there “pale cinnamon pink” 5A2 when young, becoming slightly darker in age, in midsection pubescent to velutinous, near “drab” 6C3, “wood brown” 7C4 or “Rood’s brown” 7D5-6, “walnut brown” 7D4-6, downward to base tomentose, “auburn”7E5, “Vandyke brown” 7E6, “burnt umber” 7E7, “Kaiser brown” 7E5-8, “blackish-brown(1)” 7F5, “warm sepia” 7E6, “carob brown” 7E7, “bone brown”7F5-8 or “seal brown” 8F4-5. Rhizomorphs rare, obscure, -6 × 0.5–1.0 mm, black, strap-shaped, occasionally branched; short, narrow disarticulated stipes rare to abundant. Odor strongly of garlic but ephemeral; taste strongly alliaceous, persisting in herbarium specimens.

Figure 20. 

Mycetinis copelandii. Basidiomata. Photos courtesy of Michael Wood. Standard bars = 20 mm.

Gregarious to densely gregarious, clustered to subcespitose on or among senescent leaves of Quercus, Castanopsis and Lithocarpus in mixed, coastal forests; common; October-January.

Pileipellis (Fig. 21) a roughly hymeniform layer of two types of smooth cells: 1) broadly clavate to vesciculose, sphaeropedunculate, obpyriform or irregularly lecythiform cells 13–33(-90) × 6.6–14.4(18) µm, smooth to minutely roughened, occasionally with adventitious conical to lobate outgrowths, seldom lobed or bifid, firm- to thick-walled (wall - 1 µm thick), sometimes with ochraceous to brown walls up to 1.5 µm thick; and 2) free-form lobate termini (Fig. 22), stalked (stalk 7-<50 × 3.5–6.5 µm, inconspicuously clamped), -55 µm broad; contents heterogeneous. Pileus and lamellar tramae loosely interwoven; hyphae of two types: 1) 2.5–5.5 µm diam, firm-walled, conspicuously clamped; and 2) 4.5–17 µm diam, firm-walled, usually narrowing at septa, inconspicuously clamped; contents heterogeneous. Pleurocystidia (Fig. 23) presumptive (see below), 25–44 × 4–6 µm, cylindrical to narrowly fusiform, conspicuously clamped; contents more or less homogeneous. Basidia (Fig. 24) 27–39 × 6–10 µm, usually straight and rod-like, narrowly clavate, often subtly subcapitulate, 4-sterigmate, obscurely clamped. Basidiospores (Fig. 25A) (9-)10.5–12(-17) × 3–4(4.5) µm (Q = 2.63–3.83; Q^m = 3.29; L^m = 11.75 µm), marasmioid (distally rounded, proximally tapered), sometimes slightly curved, smooth, thin-walled; contents multiguttulate. Cheilocystidia (Fig. 26) 30–48(-60) × (7-)9–15 µm (at widest point), usually significantly larger than basidia, clavate, broadly clavate to ventricose-rostrate, stalked (stalk 7–20 × 4–5.5 µm, obscurely clamped), often with adventitious apical outgrowths, thin- to firm-walled, hyaline; contents homogeneous; outgrowths usually two, stout and digitate, occasionally more complex. Stipe medullary hyphae strictly parallel, tightly packed, (2-)4–8 µm diam, firm- to thick-walled (wall -0.5 µm thick), free (without slime matrix; not adherent in sheets), obscurely clamped, hyaline. Stipe cortical hyphae 4–8 µm diam, thick-walled [wall -2 µm thick, weakly pigmented (PhC)], producing caulocystidia as side branches or hyphal termini. No stipe tissue dextrinoid. Caulocystidia from upper stipe (Fig. 25B) 20–250 × 4–10 µm, more or less equal, rounded at apex, thick-walled (wall -1.5 µm thick, weakly pigmented near origin), often prominently clamped, occasionally branched, never straight, irregularly curved or kinked, in fascicles. Caulocystidia from stipe base (Fig. 27) 20–900 µm long, in two width ranges with intermediates: 1) 5–13 µm broad, predominant, thick-walled [wall – 2 µm thick, weakly pigmented (PhC)]; and 2) 12–21 µm broad, widely scattered in fascicles of 2–4 individuals, thick-walled (wall -8 µm thick often occluding cell contents), distinctly pigmented.

Figure 21. 

Mycetinis copelandii. Pileipellis elements. A–D, G Broadly clavate individuals without outgrowths E, F, H Individuals with lobose outgrowths. Standard bars = 10 µm. TFB 8084 (TENN-F-55408).

Figure 22. 

Mycetinis copelandii Pileipellis elements. Free-form, lobose individuals. Standard bars = 10 µm. TFB 8084 (TENN-F-55408).

Figure 23. 

Mycetinis copelandii. A Immature basidium B–D Presumptive pleurocystidia. Standard bars = 10 µm. TFB 8084 (TENN-F-55408).

Figure 24. 

Mycetinis copelandii. Basidia. A Immature individual B–D Mature individuals. Standard bars = 10 µm. TFB 8084 (TENN-F-55408).

Figure 25. 

Mycetinis copelandii. A Basidiospores BCaulocystidia from upper stipe. Standard bars: A = 5 µm; B = 20 µm. TFB 8084 (TENN-F-55408).

Figure 26. 

Mycetinis copelandii. Cheilocystidia. Standard bars = 10 µm. TFB 8084 (TENN-F-55408).

Figure 27. 

Mycetinis copelandii. Caulocystidia from stipe base. Standard bar = 20 µm. TFB 8084 (TENN-F- 55408).

The free-form cells of the pileipellis are reminiscent of those of members of Gymnopus (Micromphale) sect. Perforantia and (Marasmius) sect. Androsacei but are considerably more complex. The size of the lobes are like the broader lobes of some pileipellis lobes in the same groups.

Pleurocystidia are either absent or undifferentiated. Subjective judgement on their presence is based on: 1) ubiquitous presence in other taxa of Mycetinis and related groups; 2) narrow width as compared with immature basidia of more or less equal length; and 3) no evidence of distal heterogeneous contents, as opposed to developing basidia of more or less equal length.

When comparing M. olidus with M. copelandii, Desjardin (1987a) summarized macromorphological characters considered taxonomically important in Marasmius (e.g. macroscopic features, substrate, stipe attachment, and microchemical reactions) and concluded that the two were micromorphologically indistinguishable, but M. olidus, commonly collected in eastern North America, not only produced consistently smaller basidiomata on non-sclerophyllous leaves, but is allopatric with M. copelandii. Consequently, M. olidus is treated here at species rank.

Desjardin (1987b) considered Marasmius copelandii to be the most commonly collected alliaceous marasmioid fungus in California, fruiting in mixed coniferous/tan bark oak forests and oak woodlands along the California coast from San Diego County to Mendocino County, and in similar habitats in the foothills of the Sierra Nevada, Siskiyou and Trinity mountain ranges.

A single collection of putative Ma. copelandii (TENN55408-TFB 8084, based on spore dimensions) produced ITS sequences essentially congruent with those of Ma. salalis (1bp difference/722bp). This anachronism provokes the question of morphological discrepancies (in this case largely spore dimensions) versus molecular similarity. One solution is that Ma. salalis/Ma. copelandii produces long- and short-spored forms. A more accurate assessment will be possible when additional sequences become available and/or when multigene trees are produced.

California, Santa Cruz Co., Martin Rd., Fire Station, N37°03'03.6", W122°08'19.2", 13.XII.1983, coll. AS Methven (as Marasmius siccus), annot. D.E. Desjardin (as Marasmius copelandii) ASM 2676 (TENN57185); San Mateo Co., San McDonald County Pk., N37°18'31.7", W122°15'31.9", 12.XII.1983, coll AS Methven, annot. D.E. Desjardin (as Marasmius copelandii), TENN-F- 57189;

New Zealand, North Island, Wellington, Butterfly, S41°00', E175°23', 11.III.1958, coll. M. Curran, Stevenson 1247 (K; annot. Desjardin; annot. Johnston).

1) Basidiomata diminutive (pileus 5–16 mm broad; stipe 6–15 × 0.5–1 mm); 2) pileipellis a hymeniform layer of inflated hyphal termini, often with small knobs or coralloid outgrowths; 3) cheilocystidia similar to pileipellis cells, diverticulate; 4) spores 7–8 × 4–4.5 µm, ellipsoid, collybioid (not tapered proximally or distally); 5) fruiting on rotting bark and twigs of myrtaceous hosts; 6) distribution in New Zealand.

Basidiomata (Fig. 28) diminutive, solitary or in small clusters. Pileus 5–16(-20) mm broad, strongly convex when young, expanding in age to plano-convex sometimes with a slightly depressed disc, occasionally with low, broad umbo, shallowly subsulcate at the margin, pale beige-brown with reddish brown tones when young, disc remaining so in age, becoming paler toward the margin, dull, dry, minutely furfuraceous-punctate over disc. Subpellis hyphae interwoven, 3–6.5 µm diam, firm-walled, apparently involved in a slime matrix; clamp connections sporadic, not universal. Pileus trama tough, supple when fresh, buff to pale concolorous with pileus surface; pileus tramal hyphae thin-walled to thick-walled, subgelatinous, inamyloid. Lamellae adnate to slightly decurrent, subdistant, often weakly pseudocollariate, total lamellae (23-)26–38, through lamellae 7–9, subventricose, up to 1.5 mm broad, rarely with buttresses, off-white to pale cream or pale beige, taking on slight pinkish tint upon drying and storage; lamellar edge minutely fimbriate, concolorous with lamellar face; lamellulae poorly developed, in two series. Stipe strongly curved to nearly straight, central or occasionally slightly eccentric, 6–15 × 0.5–1.0 mm, terete, cylindrical, equal or slightly attenuate downward, tough, solid, insititious to expanded at base, appearing erumpent, apex minutely pulverulent, downward appearing glabrous to sparsely silky; stipe apex cinnamon, orange-brown to dark reddish brown, downward darker to almost black near base. Rhizomorphs not observed. Odor and taste strong, like garlic.

Figure 28. 

Mycetinis curraniae. Basidiomata. A PDD 86987 B PDD 95705. Standard bars: A = 10 mm. B Ruler in millimeters. Photo courtesy J. Cooper.

Known only from New Zealand (both islands); solitary or in groups on rotting bark of twigs, living, standing trees and/or logs of myrtaceous trees (Leptospermum sensu lato, Metrosideros umbellata) (teste Horak). PDD reports nine collections from substrates Kunzea ericoides, Dacrydium cupressum and Cupressus macrocarpa; mid-summer to autumn (Jan-May)

Pileus disc pileipellis (Fig. 29) constructed of two elements: 1) repent hyphae 5-8.5 µm diam, firm- to thick-walled (wall -1 µm thick, hyaline), coarsely encrusted , obscurely clamped; and 2) inflated hyphal termini 11–22 µm broad, in an interrupted layer, stalked (stalk 3–35 × 3–9 µm), thick-walled (wall 0.7–1.4 µm thick, hyaline or occasionally weakly pigmented), usually very finely encrusted or roughened, either without outgrowths, with scattered papilla-like outgrowths (usually 1–3 × 1–1.5 µm, rounded), or with complex, branched, coralloid outgrowths 4–20 µm long, with branches 2–2.5 µm broad, repeatedly branched, flaccid. Underlying interwoven hyphae 3–6.5 µm diam, firm-walled, apparently involved in a slime matrix; clamp connections sporadic, not universal. Pleurocystidia (Fig. 30A–D) plentiful, 33–39 × 4–7 µm, narrowly fusiform to fusiform, conspicuously clamped; contents more or less homogeneous. Basidioles clavate to (occasionally) subampulliform; basidia (Fig. 30E–H) 24–35(-40) × (4-)7–9 µm, clavate, (2-)4-sterigmate, obscurely clamped; sterigmata subcornute; contents heterogeneous, multiguttulate. Basidiospores (Fig. 31) (6.5–)7–8(-10) × 4–4.5(-5) µm (Q = 1.50–2.00; Q^m 1.76; L^m = 7.4 µm), ellipsoid, flattened somewhat adaxially, smooth, thin-walled, inamyloid. Cheilocystidia (Fig. 32) locally common, 27–40 ×10–16 µm overall, stalked (stalk 5–29 × 4–9 µm, thick-walled), expanded distally to 10–16 µm broad, surmounted by a cluster of diverticula; diverticula (1-)2–7 × 1–1.5 µm, digitate, often dichotomous, hardly refringent. Stipe medullary hyphae (2-)5–11 µm diam, strictly parallel, free (not involved in a slime matrix), firm- to thick-walled (wall -2 µm thick, hyaline, often fluctuating in thickness), conspicuously clamped. Stipe cortical hyphae 4–14(-16) µm diam, thick-walled (wall -2 µm thick, pigmented yellowish), producing two types of caulocystidia (Fig. 33); 1) widely scattered narrow-necked lobes, 4–15 × 4.5–7.5 µm, hyaline, firm- to thick-walled (wall -1 µm); and 2) repent caulocystidial hairs 15->250 × 4–7.5 µm, thick-walled (wall -2 µm thick, hyaline to weakly yellowish), usually slightly subcapitulate apically, smooth to minutely roughened.

Figure 29. 

Mycetinis curraniae. Inflated pileipellis elements. A, B Structures minutely roughened but without papillate outgrowths C, D Structures with few, papillate outgrowths E, F Papillate outgrowths larger, more complex G, H Outgrowths complex, repeatedly rebranched. Line drawings represent photographs, not to scale. Standard bars = 10 µm. ZT 949 (SFSU).

Figure 30. 

Mycetinis curraniae. Hymenial structures. A–D Pleurocystidia E–H Basidia. Standard bars = 10 µm. ZT 949 (SFSU).

Figure 31. 

Mycetinis curraniae. Basidiospores. Standard bar = 5 µm. ZT 949 (SFSU).

Figure 32. 

Mycetinis curraniae. Cheilocystidia. Line drawings represent photographs, not to scale. Standard bars = 10 µm. ZT 949 (SFSU).

Figure 33. 

Mycetinis curraniae. A–D Repent caulocystidia E Strongly encrusted pileipellis hypha. Standard bars = 10 µm. ZT 949 (SFSU).

M. curraniae produces diminutive basidiomata similar to those of My. cinnamomeus, My. olidus, My. scorodonius f. diminutivus, My. virgultorum and My. yunnanensis, usually fruiting in small clusters or troops on woody material. Stevenson’s (1964) description reported features not observed subsequently, including weakly “pseudo-amyloid” (?dextrinoid) elements in pileus and lamellar tramae, pruinose stipe, “faintly amyloid” inflated pileipellis structures.

Pileipellis structures appear to be very finely roughened. This may be caused by a thin slime layer covering the pileipellis and certainly produced in the pileus trama as well. Pileipellis structures and cheilocystidia are not discretely defined and photos are difficult to interpret and depict. For this reason, line drawings are supplied to represent the structures in photos of these structures.

Desjardin and Horak (1997) drew attention to some similarities between My. curraniae and M. cinnamomeus Cleland (1934). Grgurinovic (1997) supplied a more detailed description of the latter, but by not citing a holotype, implied that a holotype (South Australia, National Park, Mt. Lofty, Willunga Hill, Innan Valley, teste Cleland) was unavailable. Desjardin and Horak (1997) concluded that My. curraniae and M. cinnamomeus were distinguishable at least as follows: 1) apparently no odor of garlic (noted as “odor none” by Cleland for M. cinnamomeus) ; 2) larger spores (9–12 × 4.5–6.0 µm teste Desjardin and Horak) of M. cinnamomeus; and 3) M. cinnamomeus fruiting on the base and bark of living Eucalyptus.

New Zealand, North Island, Prov. North Auckland., Little Barrier Island, Tinkawa Stream, S36°11'56.60", E175°04'54.73", 14.V.1981, coll E. Horak, det. DE Desjardin [as Marasmius curraniaii (sic)] Horak 949 (ZT, SFSU). New Zealand, South Island, Prov. Westland, Rotomantu, Lady Lake, S43°35'56", E171°34'41", 25.III.1983, coll E. Horak, det. DE Desjardin [as Marasmius curranii (sic)] Horak 2101 (SFSU).

Denmark, Greenland, Frederikshåb, Paamiut, N62°00', W49°40', 24.IX.1983, 25 m, coll. T. Borgen, TB.83.83 (C).

1) Basidiomata small but robust (pileus 5–23 mm broad; stipe 20–40 × 1.5–2.0 mm); 2) pleurocystidia well-developed; 3) pileus dark brown; 4) spores 11–12 × 8–9 µm; 5) stipe vestured, pruinose to pubescent; 6) boreal distribution (Greenland, Svalbard).

Basidiomata (Fig. 34) small but robust. Pileus 5-23 mm broad, at first convex with inrolled margin, later plano-convex, more rarely somewhat depressed or papillate, hygrophanous, initially unicolorous and without striation, dark brown (Munsell 5YR4/3, “bone brown” 7F8), later disk brown (Cailleux P67; 7.5YR5/4, “Natal brown” 8E6) and margin lighter (M69; 7.5YR7/4, “olive brown “ 5E5), crenulate, transient striate, matt to smooth to naked eye; context thin, supple, light gray brown. Lamellae adnate to shortly decurrent, distant, ventricose, thick, total lamellae (23-)33–35, through lamellae 7–9, up to 3 mm broad with occasional buttresses; lamellar edge smooth to minutely uneven, whitish overall or more rarely concolorous with pileus for ca 2 mm at the pileus margin, lamellae faces greyish pink (M53; 7.5YR7/2, “wood brown” 7C4), now (dried) “Dresden brown” 5E6 to “tawny olive” 5C3 on face, with “pale ochraceous buff” 4A2 to “light buff” 3A2 on edges. Stipe 20-40(-90) × 1.5–2.0 mm, central, dark reddish brown (T29; 5YR3/3, “bone brown” 7F8) to pink clay (ca 5YR6/4, “wood brown” 7C4) or café-au-lait (7.5YR5/2 X 4/2, “olive brown” 5E5 to “clove brown” 6F5), usually tapering somewhat distally, stuffed or partly hollow, not glabrous, ranging from pruinose to pubescent overall to apically pruinose with midsection smooth (?through handling) and lower stipe pubescent; lower stipe (1-5 mm from base) minutely wooly or lannose, stipe base consistently appressed-pilose, now (dried) “olive buff” 3B3 (perhaps paler when fresh). Odor strongly alliaceous, devoid of fetid components; taste similar, moderate to strong.

Figure 34. 

Mycetinis kallioneus. Basidiomata. Photo courtesy Ellen Larsson. ELS 57-17C. Standard bar = 20 mm.

Presently known from Greenland and Svalbard; collected in “dwarf scrub heathland” and in snow-bank communities, often with stipe disappearing among polytrichous moss; associated woody plants include Salix herbacea, Vaccinium uliginosum and Betula nana and non-woody taxa including Cerastium, Empetrum, Taraxacum. Silene, Dryas, Oxyria, Stellaria and Carex; reported from late July through September.

Pileipellis (Fig. 35) over pileus margin an irregular hymeniform monolayer of inflated elements, on pileus disc more interrupted and in age becoming commonly collapsed; inflated elements 17–60 × 7–18 µm, ranging from broadly clavate, mitten-shaped to coarsely lobate, usually stalked [stalk 4–35 × 3.5–5 µm, occasionally thick-walled (wall-1.5 µm thick, occasionally pigmented yellow-olive PhC)], conspicuously clamped; inflated portion 8–25 × 7–18 µm, firm-walled, smooth, not with papillate outgrowths, neither amyloid nor dextrinoid. Subtending hyphae tightly interwoven, 3–5.5 µm diam, firm-walled, hyaline, conspicuously clamped. Pileus trama loosely interwoven; hyphae 3–6.5(-8) µm diam, thin- to thick-walled (wall -0.5 µm thick), hyaline, conspicuously clamped, free (i.e. not involved in a slime or gelatinous matrix); “vascular hyphae” common, meandering through pileus and lamellar tramae, 2.5–4 µm diam, with dense, cyanophilous contents, refringent (BF). Hymenophoral trama regular-subregular, in dried material rather dark brown (30×); hyphae firm- to thick-walled (walls -0.8 µm thick), inamyloid, non-dextrinoid, conspicuously clamped. Pleurocystidia (Fig. 36) plentiful, 35–62 × 6–7 µm overall (at widest point), narrowly digitate, narrowly fusiform, usually projecting beyond basidia; base 3.5–5 µm diam, conspicuously clamped. Basidioles clavate to subcapitulate; basidia (Fig. 37) 34–55(-65) × (7-)10–12 µm, clavate, obscurely clamped, exclusively 2-sterigmate; sterigmata -9 × 2–2.5 µm (stout, subcornute); contents heterogeneous, multigranular. Basidiospores (Fig. 40B) (9-)11–12(-13) × (7-)8–9(-9.5) µm (Q = 1.18–1.63; Q^m = 1.35; L^m = 11.3 µm), amygdaliform (low hump on abaxial surface, often sublimoniform distally), smooth, thin-walled, inamyloid; contents sometimes uniguttulate. Cheilocystidia (Fig. 38) plentiful on lamellar edge but not rendering the edge sterile, 25–50 × 12–17 µm overall, stalked (stalk 7–35 × 3–4 µm, conspicuously clamped, firm-walled), distal portion expanded to broadly clavate,10–14 µm broad, occasionally bifurcate with lobes rounded, rarely irregularly complex-lobate. Stipe medullary hyphae free (not involved in slime matrix), conspicuously clamped, of three types: 1) 7–14 µm diam, thin-walled; contents heterogeneous; 2) 2–5.5, thin-walled, contents homogeneous; and 3) “vascular hyphae” 3–6.5 µm diam, refringent (PhC), cyanophilous. Stipe corticial hyphae filamentous, 2.5–5.5 µm diam, thin- to firm-walled, tightly packed, strictly parallel, weakly pigmented, producing side branches. Caulocystidia from stipe apex (Fig. 39) cheilocystidial, gathered in clusters, stalked; stalk 5–16 × 3–4 µm, conspicuously clamped, distally expanded into broadly clavate to lobate shapes, 9–12 µm broad, firm-walled. Caulocystidia from lower stipe (Fig. 40A) filamentous, 10->150 × 3.5–5.5 µ, firm- to thick-walled (wall -0.7 µm thick, hyaline), arising as side branches of stipe cortical hyphae, bluntly rounded apically, rarely straight, usually bent or gnarled, without internal clamp connections.

Figure 35. 

Mycetinis kallioneus. Pileipellis structures. A, B Overview of irregular hymeniform layer C–I Individual pileipellis elements. Standard bars = 10 µm. TB 85-209 (TUR).

Figure 36. 

Mycetinis kallioneus. Pleurocystidia. Standard bars = 10 µm. TB 85-209 (TUR).

Figure 37. 

Mycetinis kallioneus. Basidia. Standard bars = 10 µm. TB 85-209 (TUR).

Figure 38. 

Mycetinis kallioneus. Cheilocystidia. Standard bars = 10 µm. TB 85-209 (TUR).

Figure 39. 

Mycetinis kallioneus. Caulocystidia from stipe apex. A Cluster of caulocystidia B–K Individual caulocystidia. Standard bars = 10 µm. TB 85-209 (TUR).

Figure 40. 

Mycetinis kallioneus. ACaulocystidia from lower stipe surface B Basidiospores. Standard bars: A = 20 µm; B = 5 µm. TB 85-209 (TUR).

For a discussion of pleurocystidial identification see Materials and Methods under taxonomic characters.

Identification of cheilocystidia is based on two points: 1) experience with other taxa in Mycetinis and other marasmioid and micromphalioid has shown such relatively rudimentary cheilocystidial structures, although some species of Mycetinis exhibit broom cell-like cheilocystidia; and 2) cheilocystidial structures described and illustrated here are limited to lamellar edge and are of greater diameter than basidia and are ventricose-rostrate, not gradually clavate as basidia.

The small pustules of cheilocystidioid caulocystidia at the stipe apex seem unique in the genus. The structures themselves are not surprising, because such resemblance is found in phylogenetically widely separated fleshy fungi (i.e. Strobilomyces, Hymenopellis).

Denmark, Greenland, Frederikshåb, Paamiut, N62°00', W49°40', 19.viii.1985, coll. T. Borgen, TB.85.209 (TUR 040959, topotype). Norway, Svalbard, Longyearbyen, mouth of Blomsterdalen, N78°14', E15°30', 5.VIII.1983, coll. S. Huhtinen (as Marasmius sp.), SH 83/267 (TUR 079363); same location, 31.VII.1983, coll & det S. Huhtinen, SH 83/141 (TUR 079364); Isfjorden, west side of Grønfjorden, Kongressdalen, middle part, N78°02', E14°07', 19.VIII.1966, coll. Esteri Kankainen (as Marasmius sp.), s.n. (TUR 079366); Vestspitsbergen, Kongsfjorden, southeast of Ny Ålesund, N78°55', E12°02', 24.VIII.1966, leg E. Kankainen, s.n. (TUR 072364).

United States, Michigan, Oakland Co., Proud Lake [N42°33'42", W83°31'43"], 1.XI.1970, coll W.W. Patrick, Gilliam 997, (MICH).

1) Basidiomata diminutive (pileus 3-18 mm broad; stipe 12–31 × 0.4–2.1 mm; 2) vestured, grayish brown stipe; 3) curved-clavate spores 10–16 µm long; 3) fruiting habitat on fallen Pinus needles and Quercus leaves; 4) penetrating odor of garlic; 5) distribution in eastern United States from Michigan to Tennessee and North Carolina, south to central Florida.

Pileus 3–18 mm broad, pulvinate or convex at first, then plano-convex and often umbilicate, finally plane or convex with a wavy margin, dry, dull, opaque or matt, minutely velutinous particularly on the disc; margin entire to sulcate-striate nearly to disc, pliant, reviving; disc moderate brown in primordia, soon light yellowish brown (Maerz & Paul 11D4-5), “grayish olive” 30C3 outward “pale olive buff” 3B2, often tinged pink, or moderate brown on the disc and light yellowish brown elsewhere. Pileus trama thin (-1.5 mm thick), firm, yellowish white. Lamellae distant, adnexed or subdecurrent, narrow (0.6–1.5 mm broad), thin, distant, moderately numerous (through lamellae 15–20), unequal, with 2–3 irregular tiers of lamellulae, sometimes seceding in age, membranous, often subventricose, entire or minutely fimbriate, straight, occasionally somewhat intervenose, rarely forked near the stipe, light yellowish brown (M&P 11B4) to “tilleul buff” 7B2, in drying becoming concolorous with mature pilei to distinctly “cinnamon” 6B5 or avellaneous (?necropigment). Stipe 12–31(-35) mm long, 0.5–2.1 mm thick, central, terete or flattened at the apex, tapered slightly to the base, straight or curved, dry, dull, opaque, hollow, cartilaginous, even, pruinose above, tomentose below, concolorous with lamellae, yellowish white or light yellowish brown up to 2 mm from the apex downward, moderate brown, grayish brown tinged pink, “wood brown” 7C4 to “buffy brown”6D4 or blackish brown below; not insititious; vesture whitish at stipe apex, downward brownish pink. Sterile stipes occasionally present along the leaf veins near basidiomata, tapered, glabrous, yellowish brown. Rhizomorphs lacking or rare, extremely slender (0.1–0.3 mm broad), -8 mm long, curly, unbranched, black. Basal mycelium on hardwood leaves sometimes forming a flat disc, often visible near the leaf veins as well, fine, resembling spun glass, white. Odor weakly pleasant to pungent, of garlic. Taste of garlic or onion, often persisting in drying and storage.

Gregarious on duff of Pinus strobus and P. resinosus and on midribs of hardwood leaves, usually Quercus (teste Gilliam 1975); eastern North America from Ontario/Quebec south to Gulf Coast; May to November.

Pileipellis constructed of three interlocking types of structures: 1) pileal hairs (Fig. 41) as side-branches of repent pileipellis, -75 × 4–8(-14) µm, thin- to firm-walled, minutely roughened (perhaps resinous), usually subcapitulate; 2) inflated hyphal termini (Fig. 42) broadly clavate, subglobose, to spheropedunculate, (9-)20–36(-42) × (4-)11–21)-24) µm, usually thick-walled (wall -1.0 µm thick, occasionally weakly pigmented), occasionally with lobose apical outgrowths; and 3) free-form hyphal segments (Fig. 43), often quite extensive, firm-walled, with lobes and extended arms, occasionally internally septate, sometimes with internal clamp connections. Pileus and lamellar tramae loosely interwoven; hyphae 3–7.5 diam, thin-walled, occasionally clamped. Pleurocystidia (Fig. 44) 14–32 × 6.5–8.5 µm, generally fusiform with rounded apex, conspicuously clamped; contents more or less homogeneous. Basidia (Fig. 45) 19–26(-29) × (4-)7–10 µm, clavate, hardly capitulate, 4-sterigmate, obscurely clamped; contents heterogeneous, multiguttulate; sterigmata slender, spindly. Basidiospores (Fig. 49A) (8-)11–16 × (2.8-)3.5–4(-4.5) µm (Q = 2.00–3.67; Q^m = 2.93; L^m = 11.7 µm), marasmioid (distally rounded, proximally tapered), thin-walled, inamyloid; contents minutely granular. Cheilocystidia (Figs 46, 47) rare to plentiful, occasionally probably rendering lamellar edge sterile, 28–45 × 10–16 µm (at widest point), stalked (stalk 5–30 × 3.5–5 µm, obscurely clamped), expanded distally, ranging in shape from obpyriform, to obpyriform with one or more large lobes or digitate diverticula, hyaline, thin- to firm-walled; contents more or less homogeneous. Stipe medullary hyphae 3–9 µm diam, strictly parallel, nonamyloid, thin-walled. Stipe cortical hyphae 2–8.5 µm diam, nonamyloid, thick-walled (wall -2 µm thick, pigmented pale yellow to moderate reddish brown, immediately weakly yellow-olive in 3% KOH (BF). Caulocystidia (Figs 48, 49B) -150 × 2.5–8.5 µm, arising as side branches or termini of stipe surface hyphae, thick-walled (wall – 2.5 µm thick, hyaline to moderate brown, light olive green in KOH), scattered on stipe apex, downward more densely gregarious, toward stipe base gathering into synemmatoid columns of -150 individuals, appearing hirsute; stipe base strigose.

Figure 41. 

Mycetinis olidus. Pileal hairs. Standard bars = 10 µm. MG 1973 (MICH-F- 0051239).

Figure 42. 

Mycetinis olidus. Inflated pileipellis structures. Standard bars = 10 µm. DED 4529 (TENN 57177).

Figure 43. 

Mycetinis olidus. Free-form pileipellis structures. Outlines furnished to better interpret photographs. Standard bars = 10 µm. DED 4529 (TENN 57177).

Figure 44. 

Mycetinis olidus. Pleurocystidial structures. Standard bars = 10 µm. VA 97 257 (TENN 50012).

Figure 45. 

Mycetinis olidus. Basidia. Note heterogeneous contents. Standard bars = 10 µm. DED 4529 (TENN 57177).

Figure 46. 

Mycetinis olidus. Clavate cells from lamella edge. Standard bars = 10 µm. DED 4529 (TENN 57177).

Figure 47. 

Mycetinis olidus. Cheilocystidia. Standard bars = 10 µm. MG 1973 (MICH-F-0051239).

Figure 48. 

Mycetinis olidus. Caulocystidial structures. A Arrangement of caulocystidia on stipe surface BCaulocystidia. A = not to scale. B Standard bar = 10 µm. VA 97 257 (TENN 50012).

Figure 49. 

Mycetinis olidus. Caulocystidia and basidiospores. A Basidiospores (DED 4529) BCaulocystidia (VA 97 257). Standard bars: A = 5 µm; B = 20 µm. VA 97 257 (TENN 50012).

Interpretation of structures and terminology can be summarized as follows. 1. Gilliam (1975b) chose not to use the term cheilocystidia for clavate cells found “present on the lamellar edges only,” and not projecting beyond basidia. Such cells are scattered along the lamellar edge, sometimes indistinguishable from immature basidia except for cell breadth (10–16 µm broad for clavate cells versus 8–10 µm broad for basidia). Usually, however, frequent cheilocystidial cells form lobes or diverticula, immediately distinguishing them from basidioles. 2. Pleurocystidia are either absent or indistinguishable from basidioles before the latter have developed heterogeneous contents and clavate shape. For similar conclusions, see under My. copelandii. 3. Other eastern North American taxa on Quercus leaves = Gymnopus (sect. Perforantia) foliiphilus, G. inflatotrama nom. prov., G. novomundi nom. prov. (Androsacei) and M. straminipes. 4. “Sterile stipes” (teste Gilliam 1975) are reminiscent of M. opacus, in which sterile stipes are common but interpreted as rhizomorphs (Desjardin et al. 1993). 5. Caulocystidial wall thickness is not visible in PhC, but with IKI and BF, the inner surface of the wall becomes visible because the hyper-refringency of the caulocystidia disappears.

Desjardin (1989) provided type specimen descriptions of Marasmius copelandii Peck and M. olidus Gilliam. Desjardin (1987a) concluded that the differences between M. olidus and M. copelandii did not warrant species rank, and reduced Gilliam’s epithet as M. copelandii var. olidus. According to Index Fungorum, Gilliaim’s epithet (as Marasmius olidus or M. copelandii var. olidus) has not been transferred to Mycetinis. Here, the differences from My. copelandii appear significant enough to accept My. olidus as a separate species within Mycetinis. The two taxa share the following: 1) strong odor and taste of garlic; 2) vestured stipe; 3) spore statistics; 4) doubtfully differentiated pleurocystidia; 5) basically clavate cheilocystidia; 6) inflated pileipellis elements. Differences between My. olidus and My. copelandii can be listed as follows: 1) basidiomata of My. olidus consistently smaller and less robust that those of My. copelandii; 2) pileipellis free-form cells appear to be of different shape and extent; 3) lamellae distant (My. olidus) versus close to crowded; 4) cheilocystidia are doubtful in My. olidus, but when observed, they range from those figured by Gilliam to broadly fusiform and submammilate; 5) fruiting habitat on Quercus leaves; 5) distribution in eastern North America.

Alexander Smith’s preliminary identification of MICH-F-005239 (paratype of My. olidus) as M. prasiosmus may have been predicated on habitat (i.e. on fallen Quercus leaves) and advice from his professor, Calvin Kauffman. Here, My. prasiosmus (= My. querceus) is accepted in Mycetinis, but for an apparent European taxon, basidiomata of which are significantly larger than those of My. olidus, and the micromorphology of which is quite different from that of My. olidus, especially spore size and shape.

Redhead (1982) correctly reported that “pigmented hyphal walls” of stipe cortex of My. olidus (as Marasmius) showed a color change to greenish gray in KOH solution. This reaction was also reported for M. prasiosmus, but this is true only for Kauffman’s concept of this name, for which M. olidus was later introduced. The American concept of M. prasiosmus is quite different from the European organism treated here as M. prasiosmus, in which the color reaction is missing.

United States, Florida, Alachua Co., vic. Gainesville, San Felasco State Park, Planera Hammock, Hwy 232, N29°47'00.2", W82°27'58.0", 12.XII.1987, coll DE Desjardin, TFB DED 4529 (TENN57177). Michigan, Livingston Co., vic. Pinckney, E.S. George Reserve, N42°27'30.88", W84°00'41.34", 4.X.1936. coll. A.H. Smith (AHS5034, as M. prasiosmus), det. M. Gilliam (as M. olidus) (MICH-F-00051235, paratype); Oakland Co., Proud Lake, N42°33'42", W83°31'43", 1.XI.1970, coll W.W. Patrick, Gilliam 997, (MICH-F-11400, holotype, p.p.); Proud Lake, N42°33'42", W83°31'43", 15.X.1955, coll. AH Smith (AHS51125) (as Marasmius prasiosmus), det. M. Gilliam (as M. olidus) (MICH-F- 0051239; paratype); Milford, 15.IX.1938, N42°35'32", W83°36'05", coll. A.H. Smith (AHS10936, as M. prasiosmus), det. M Gilliam (as M. olidus) (MICH-F-0051237, paratype); Haven Hill, N42°38'27.56", W83°33'48.28", 11.X.1956, coll. A.H. Smith (AHS62192, as M. prasiosmus), det. M. Gilliam (as M. olidus) (MICH-F- 00051238, paratype); Washtenaw Co., Ann Arbor, N42°16', W83°44', Cascade Glen, 17.IX.1907, coll. & det. C.H. Kauffman (as M. prasiosmus), s.n. (MICH-F-00051241); vic. Chelsea, Mill Lake, N42°19'44", W84°05'22", 26.VIII.1972, coll. A.H. Smith (s.n., as M. prasiosmus), det. M. Gilliam (as M. olidus, MG 1549 (MICH-F- 0051243, paratype); vic. Dexter, Silver Lake, N42°25'13", W83°57'35", 2.X.1936, coll. A.H. Smith (AHS5004, as M. prasiosmus), det. M. Gilliam (as M. olidus) (MICH-F- 00051244, paratype); vic. Dover, Silver Lake, N42°25'13", W83°57'35", 23.IX.1938, coll. A.H. Smith,(AHS11057, as M. prasiosmus ss. Kauffman), det. M. Gilliam (as M. olidus) (MICH-F-0051245; paratype). North Carolina, Swain Co., GSMNP, Kephart Prong Trail, N35°35'23.7", W83°21'49.2", 25.VII.1991, coll V Antonín, VA 97/257 (BRNM; fragment TENN50012); Tennessee, Blount Co., GSMNP, Metcalf’s Bottoms, N38°40'54.1", W83°38'56.7", 24.V.2013, coll. Sam Morris, TFB 14211 (TENN68071).

United States, South Carolina, Darlington Co., Society Hill, N34°30'47", W79°51'03", VI, Curtis 1241 (FH, K).

1) Basidiomata of moderate size, gracile (pileus 3–20 mm broad; stipe 10–45 × 1.5–2.5 mm); 2) rhizomorphs usually plentiful, slender, pallid, usually erect; 3) pleurocystidia fusiform, usually submammilate; 4) cheilocystidia arbuscular with coarse branches, not setulose; 5) pileipellis microstructures differing significantly from pileus margin to disc; 6) odor and taste negligible (not alliaceous); 7) distribution in eastern North America (with some extralimital reports); 8) fruiting chiefly on dead Rhododendron twigs and leaves.

Basidiomata (Fig. 50) of moderate size, marcescent, reviving. Pileus 3–15(-20) mm diam, convex with decurved margin when young, expanding with age to plano-convex or sometimes plane with decurved or uplifted margin; disc rarely subumbonate, sometimes slightly depressed; margin entire when young, remaining so throughout maturation or becoming striate to rugulose-striate in age; surface smooth, sueded-like, dry, opaque, finely powdery or granulose overall when young, disc remaining so in age and margin sometimes becoming glabrous; when young, disc colored “pale vinaceous fawn”6C2-3, “drab” 6D3, “hair brown” 6D-E3, near “Rood's brown” 7D5, “chestnut brown” 7D-E4-5, or “clove brown” 7F3-4, with a slightly paler margin, with maturation disc region retaining greyish brown tones or fading to “vinaceous buff” 6C3-4, pale greyish yellow 5D3, pale brownish orange 5C3-4, “pale vinaceous fawn” 5-6B3, “pale cinnamon pink” 5A2, or “pale yellow-orange” 4A3, margin in age fading to ”tilleul buff” 5-6B2, “pale pinkish cinnamon” 6A2, “pale cinnamon pink” 5A2, “pale yellow-orange” 4A3, pale greyish buff or white; in age pileus typically with a pale greyish brown disc region and white margin, in wet weather entire pileus sometimes becoming white. Context thin (<1 mm), buff. Lamellae adnate or shallowly adnexed, subdistant, total lamellae 12–18, non-intervenose to somewhat so, especially near pileus margin, seldom forked, sometimes wavy in outline, non-marginate, white, buff, “pale ochraceous buff” 4A2, not discoloring. Stipe 10–40 (-45) × 1.5–2.5 mm, central, terete or seldom compressed, equal, solid at first becoming hollow in age, pruinose to pubescent or fibrillose overall or with furfuraceous base, insititious, tough; apex buff, pinkish buff, “pale cinnamon pink” 5B2-3 or near “tawny olive” 5C4, base brownish grey 5C2-3, “drab” 6D3, “hair brown” 6-7D-E3, “buffy brown” 6-7D4-5 “fuscous” 6E4, “chestnut brown” 6-7E4. Rhizomorphs (Fig. 50) abundant, well-developed, cord-like, ranging from buff to orange white to pale brownish orange, greyish brown or light brown, often branched and forming tangled masses. Odor not distinct or faintly sweet; taste not distinctive.

Figure 50. 

Mycetinis opacus. Basidiomata. ATFB 11769 (TENN-F-59880) BTFB 12467 (TENN-F-60541). Standard bars: A = ruler in millimeters. B = 20 mm.

Scattered or gregarious on fallen twigs and leaves of Rhododendron maximum and Tsuga canadensis, rarely on debris of Quercus spp., Pinus spp or undetermined deciduous hardwoods; common in temperate eastern North America, rare in southwestern United States and Japan. Known U.S. distribution: Arizona, Connecticut, Georgia, Illinois, Missouri, New Jersey, New York, North Carolina, Pennsylvania, South Carolina, Tennessee, Texas, Virginia, West Virginia.

Pileus margin pileipellis a modified rameales-structure, composed of two conspicuously clamped elements: 1) hyphae repent, diverticulate (Fig. 52A–C), 3–5.5 µm diam, firm-walled, producing side branches; side branches 2–7 × 3–4 µm diam, broadly digitate or cylindrical, often dichotomous; and 2) broom cell-like pileocystidia (Fig. 52D–G) 31–42 × 9–14 µm overall, arbuscular, stalked (stalk 4–35 × 3.5–5.5 µm, firm-walled, clamped at base), unexpended distally, producing apical branches irregularly in 360°(branches 2–7 × 3–4.5 µm, rounded at apex, rarely dichotomous); branches resembling those of diverticulate hyphae, often evacuating but not collapsing (i.e. remaining as “exoskeletons” in pileipellis). Pileus disc pileipellis constructed of the following: 1) occasional pileal hairs (Fig. 51) 10–80 × 3.5–5.4 µm, cylindrical, arising as side branches of repent hyphae, often minutely roughened, usually subcapitulate; 2) an irregularly hymeniform layer of inflated hyphal termini (Fig. 53) 14–34 × (6-)8–15 µm, ranging from digitate, gnarled-digitate, ellipsoid to broadly clavate, almost always thick-walled over inflated portion [wall -1.5 µm thick, refringent (PhC), sometimes vaguely pigmented yellowish], obscurely clamped, apparently immersed in a thin slime matrix; 3) widely scattered pileocystidia as in pileus margin, but generally crumpled and difficult to recognize; and 4) underlying a thicker tightly interwoven thatch of hyphae 3–7 µm diam, smooth, thick-walled (wall -1 µm thick, not gelatinized), conspicuously clamped. Pileus trama hyphae interwoven. Hymenophoral trama regular; hyphae 3.0–8.0 µm diam, filamentous, smooth or encrusted nearest the pileipellis, non-gelatinous, hyaline or subhyaline, inamyloid, thin- to thick-walled (up to 1.5 µm thick). Pleurocystidia (Fig. 54) common, 22–28 × 6–7 µm, fusiform to narrowly fusiform, usually submammilate, conspicuously clamped; contents homogeneous with 1–2 vaguely vacuolated areas in mid-section. Basidioles clavate to ampulliform; basidia (Fig. 55) (16-)25–31 X (5-)8–10 µm, clavate, often subcapitulate, 4-sterigmate, clamped; contents multi granular to multiguttulate. Basidiospores (Fig. 58B) (6.5-)7.5–10(-11) × (2.8-)3.5–4.5(-5) µm (Q = 1.50–2.43; Q^m = 1.98; L^m = 8.23 µm), ellipsoid to subamygdaliform, flattened somewhat adaxially, collybioid (hardly tapered proximally), thin-walled, inamyloid; contents often multigranular. Cheilocystidia (Fig. 57) 17–36 × 4.0–8.5 µm, resembling broom cell-like pileocystidia, sporadic (often absent, apparently produced on selected basidiomata), very variable, ranging from (occasionally) irregularly fusiform to bifurcate to (usually) stalked (stalk 7–17 × 3–5.5 µm, obscurely clamped, firm-walled), not expanded distally, producing a cluster of gnarled-digitate diverticula; diverticula 2–8 × 2–2.5(-3) µm, rounded at apex, occasionally inflated somewhat and occasionally dichotomous. Stipe medullary hyphae monomitic, 2.0–4.5(-6.0) µm diam, strictly parallel, free (not involved in slime matrix or adherent in sheets), firm- to thick-walled (wall -1.5 µm thick, hyaline), conspicuously clamped. Stipe cortical hyphae cylindric, ranging from hyaline (stipe apex) to pale yellow (stipe base), non-encrusted, inamyloid, thick-wlled (wall -1.5 µm thick). Stipe vesture a poorly developed Rameales-structure with numerous, erect caulocystidia; caulocystidia (Fig. 58A) digitate to vermiform, often cudgel-shaped, similar to pileus hairs, mostly hyaline and thin-walled on stipe apex, pale yellowish brown to brownish orange and thick-walled (wall -1.5 µm thick) near stipe base. Rhizomorph tissue similar to that of stipe; rhizomorph medullary and cortical hyphae undifferentiated, parallel or subparallel, firm- or thick-walled. Rhizomorph vesture absent, in some areas composed of a thin layer of loosely interwoven, irregular-shaped hyphae with scattered, short and broad diverticula.

Figure 51. 

Mycetinis opacus. Pileal hairs. Standard bars = 10 µm. TFB 14629 (TENN-F-69344).

Figure 52. 

Mycetinis opacus. Pileipellis elements. A–C Diverticulate hyphae. D–G Broom cell-like pileocystidia. Standard bars = 10 µm. TENN-F-69344.

Figure 53. 

Mycetinis opacus. Pileipellis elements; thick-walled inflated hyphal termini. A Perpendicular view of hymeniform epicutis B Side view of a small cluster of inflated elements C–J Individual thick-walled, inflated hyphal termini. Standard bars = 10 µm. TFB 14629 (TENN-F-69344).

Figure 54. 

Mycetinis opacus. Pleurocystidia. Note submammilate apices. Standard bars = 10 µm. TFB 14629 (TENN-F-69344).

Figure 55. 

Mycetinis opacus. Basidia. Note multigranular contents. Standard bars = 10 µm. TFB 14629 (TENN-F-69344).

Figure 56. 

Mycetinis opacus. Ampulliform hymenium structures. A Basidium with ampulliform shape B–H Sterile ampulliform structures. Standard bars = 10 µm. TFRB 14629 (TENN-F-69344).

Figure 57. 

Mycetinis opacus. Cheilocystidia. A Cluster of three cheilocystidia B, C Simple cheilocystidia D–K Arbuscular broom cell-like individuals. Standard bars = 10 µm. TFB 14629 (TENN-F-69344).

Figure 58. 

Mycetinis opacus. ACaulocystidiaB Basidiospores. Standard bar: A = 20 µm; B = 5 µm. TFB 14629 (TENN-F-69344).

Three characters are inconspicuous but diagnostic: 1) pleurocystidia are usually submammilate, unlike the acute forms found in sect. Androsacei and sect. Perforantia; 2) cheilocystidia are generally of the siccus-type, but branches are coarse and not setulose; and 3) pileipellis microstructures differ significantly from pileus margin to disc.

Basidiomata are usually accompanied by numerous rhizomorphs, often as tall as stipes (or taller), unlike other members of the clade in which rhizomorphs, if present, are short and extremely thin (but pallid, unlike the black or dark brown of the rhizomorphs of sects. Androsacei and Perforantia).

Although the term used to describe pileipellis elements is the same as that used in Marasmiellus sect. Rameales (“ramealis-structure”), the two structures are significantly different. In its original use, the term represents a structure in which setulae are usually 2–5(-8) × 0.7–1.2 µm (i.e. Marasmiellus appalachianensisTFB 14610, MS; Ma. ramealisTFB 4727 Sweden), while the side branches and arbuscular apical branches in Mycetinis are appreciably coarser, 2–10 × 2–3 µm. In fact, Desjardin (1997: figs 6–11) included Ma. appalachianus Desjardin together with Ma. opacus (see Desjardin et al. 1993: figs 10–16) in subsect. Opacini, although pileipellis structures are quite different.

In the most detailed discussion of Ma. opacus thus far (Desjardin et al. 1993) the following was reported: “ Features diagnostic for M. opacus include: (a) convex, rugulose-striate pileus colored pale greyish brown on the disc and white on the margin; (b) subdistant, narrow, white to buff-coloured lamellae; (c) pubescent, insititious stipe with pallid apex and brownish grey base; (d) buff or pale greyish brown rhizomorphs; (e) basidiospore mean of 8.3 × 3.7 µm; (f) diverticulate cheilocystidia; (g) pileus disc with clavate to sphaeropedunculate, often thick-walled terminal cells, and pileus margin a Rameales-structure; (h) caulocystidia similar to pileipellis elements; (i) clamped, inamyloid hyphae; and (j) fructification on leaves and wood of Rhododendron, Quercus and Tsuga.” This diagnosis, however, was compiled to distinguish Ma. opacus from other Marasmiellus taxa, but not from other taxa of Mycetinis, which, after all, was not recognized as a discrete generic unit at that time.

Desjardin et al. (1993) included discussion of cultural and sexual compatibility studies and cited numerous examined specimens. Little need be added. Later, Desjardin (1997) summarized Marasmiellus taxa from the southern Appalachian Mountains, placing Ma. opacus in section Rameales subsection Opacini Singer.

Presumably, Singer’s [“1949" (1951)] placement of Marasmiellus opacus in Marasmiellus sect. Rameales presumed its conformity to the description of the section, which was attributed to Lange (1921) as “sect. Ramealis gen. Marasmii”, the type species of which was Marasmiellus ramealis (Bull. ex Fr.) Singer [≡ Agaricus ramealis Bull.: Fr] a combination transferred concurrently. Singer (1973) proposed Marasmiellus sect. Rameales subsect. Opacini to accommodate several neotropical taxa but a description of M. opacus was furnished as extra-limital. Singer (1973) summarized Marasmiellus in neotropical regions and included section Rameales Singer, which he had proposed in 1951 (Lilloa 22: 299. “1949"). Within sect. Rameales, he (Singer 1973: 102) proposed subsection Opacini, typified by Marasmius opacus Berk. & M.A. Curtis, even though he did not explain his choice of type, nor did he take up the species. Singer’s (1973) later description of Marasmiellus opacus supplied needed taxonomic information, and among the specimens he examined were some from the southeastern United States (but with no illustrations). From all this, there is no evidence that he intimately knew M. opacus, only that he did not consider its presence in the neotropics. At the same time, subsection Opacini included eight species, so subsect. Opacini was not monotypic.

Japan, Tottori Pref., N35°30'35", E134°14'09", Kokufu Town, 4.X.1989, coll. RHP (annot. DE Desjardin), TFB 2400 (TENN-F-48740). United States, Georgia, Rabun Co., vic. Clayton, Warwoman Dell Picnic Area, N34°54'52.62", W83°21'14.21", 18.VII.1989, coll. S.A. Gordon, TFB 2788 (TENN-F- 48710); Mississippi, Harrison Co., vic. Saucier, Tuxachanie Hiking Trailhead, N30°39'43.61", W89°08'14.70", 10.VII.2014, coll. RHP, TFB 14490 (TENN-F-69190); North Carolina, Buncombe Co., Asheville, Blue Ridge Parkway, N35°34', W82°29', milepost 363, 4.VIII.1959, Coll. L.R. Hesler, TENN-F-23348); Macon Co., vic. Highlands, road to Cliffside Lake, end of road, N35°04'50.01", W83°14'03.07", 8.VII.2016, coll AS Methven, TFB 14629 (TENN69344); Highlands Biological Station, N35°04'43.99", W83°14'12.69", 19.VI.1963, coll. L.R. Hesler (TENN-F-25556); Tennessee, Blount Co., GSMNP, Cades Cove, N35°33'46", W83°50'50, 22.V.2005, coll. J.L. Mata, JLM 1601 (TENN-F-61960); vic. Townsend, GSMNP, Turkey Pen Trailhead, N35°36'41.84", W83°44'48,29", coll. RHP, TFB 13650 (TENN-F-63084); Sevier Co., GSMNP, Indian Gap, N35°36'36.09", W83°26'19.24", 2.VIII.1936, coll. L.R. Hesler (TENN-F-10199).

(Neotype, hic design.). Sweden, Västergötland, Mölndal Parish [N57°30'00", E12°01'00"], Gummebo, 5.X.1940, coll. T. Nathorst-Windahl (no. 2313), Fungi Exsiccati Suecici no. 1155 (S, BPI and presumed other distributions).

1) Basidiomata of moderate size, gracile (pileus 15–28 mm broad; stipe 60–100 × 1.5–4 mm); 2) lamellae close to crowded; 3) stipe vestured over all; 4) pileipellis a hymeniform layer of inflated, ventricose-rostrate cells; 5) cheilocystidia not differentiated; 6) long, individual caulocystidia arising from a turf of cespitose, shorter individuals; 7) fruiting on rotting deciduous leaves; 8) distribution from Scandinavia to Italy.

See Appendix 2 for rationale of inclusion.

Basidiomata (Fig. 59) of moderate size, gracile. Pileus (5-)15-28(-40) mm broad, convex, then applanate, with slightly involute then straight margin, hygrophanous, pale brown to reddish brown, drying to near “chamois” 4B4, smooth to suede-like, or sometimes slightly rugulose or grooved at margin when old; margin translucently striate 1–2 mm, when moist. Context relatively thin, white or brown. Lamellae adnate, slightly anastomosing when old, thin, ventricose, -2.5 mm broad, characteristically crisped when dried, seceding on drying and then appearing weakly pseudocollariate, now taffy colored with somewhat paler edge, total lamellae 70–80, through lamellae 18–28; lamellulae usually in one rank (rarely two). Stipe (20-)60–100 × 1.5–4 mm, terete to compressed, gradually tapering upward, slightly broadened above, straight or often curved at base, fistulose to lightly stuffed, upward avellaneous-tan to brown, downward becoming duller brown, paler at apex, darker at base, entirely white pruinose to pubescent, sublannose villosity ranging from overall to sparse upward, extirpated by handling in midsection and resuming downward with dirty white to brown basal mycelium; stipe apex revealed by seceding lamellae white (not dark brown as in typical Marasmius); stipe base strigose, non-insititious, disappearing into surface of substrate. Rhizomorphs (see Antonín and Noordeloos 2010, fig. 119) rarely reported, apparently very slender, pallid, curly, probably not branched. Odor strong, of garlic; taste with distinct garlic component.

Figure 59. 

Mycetinis prasiosmus. Basidiomata. A TU 118971 B TU 101659. Standard bars: A = 20 µm; B not to scale. Photos courtesy Urmas Kohljalg.

Fruiting chiefly on decaying Quercus leaves but occasionally on other deciduous leaves(i.e. Fagus, Betula, Carpinus, etc.); widely distributed through Scandinavia and continental Europe; Autumn to late Autumn.

Pileipellis (Fig. 60) including pileus margin a more or less hymeniform layer of inflated hyphal termini; inflated elements (14-)20–40 × (7-)10–22 µm, staked (stalk 6–16 × 5–8 µm), ranging from obpyriform, vesciculose, ventricose-rostrate to broadly clavate, mitten-shaped or lobate, conspicuously clamped, firm walled, hyaline or occasionally weakly pigmented. Pleurocystidia (Fig. 61A–D) 32–46 × 4–7 µm (at widest point), narrowly to broadly fusiform, stalked, conspicuously clamped. Subhymenial hyphae branched, thin-walled, 2.5–4.0 µm diam. Pileus and hymenophoral trama subregular to irregular; hyphae cylindrical or slightly inflated, hyaline, thin-walled, 2.0–14(20) µm diam. Basidioles 19–38 × (3.0)4.5–10 µm, cylindrical to subampulliform; basidia (Figs 61E–H, 62) (26-)30–38 × (5.0-)6.0–10 µm, cylindrical or clavate, hardly subcapitulate, (2-)4-sterigmate, conspicuously clamped; contents heterogeneous, appearing oily. Basidiospores (Fig. 63B) (7-)9–10.5(-12.5) × (3.5-)4–5.5(-6) µm (Q = 1.63–2.25; Q^m = 1.97; L^m = 9.2 µm), ellipsoid to elongate pip-shaped, tapered slightly proximally, thin-walled, inamyloid; contents more or less homogeneous. Lamellar edge fertile; cheilocystidia undifferentiated, but clavate to subampulliform structures present. Stipe medullary hyphae strictly parallel, free (not involved in slime matrix), of two types: 1) 6–15 µm diam, firm- to thick-walled (wall -2 µm thick, hyaline), obscurely clamped; and 2) 2–4 µm diam, thick-walled (wall -1 µm thick, weakly pigmented), seldom but conspicuously clamped. Stipe cortical hyphae 3–5 µm diam, thick-walled (wall -1.5 µm thick, weakly pigmented), seldom and obscurely clamped, producing caulocystidia as side branches. Caulocystidia (Fig. 63A) of two types: 1) 20–45 × 7–9.5 µm, gnarled, thick-walled (wall -1.0 µm thick, hyaline), occasionally branched, in a turf; and 2) 49–120 ×7–10 µm, sinuous, occasionally branched, rarely internally clamped, thick-walled (wall –1.0 µm thick, hyaline to weakly pigmented); caulocystidia on lower stipe retaining the basic turf but with densely gregarious (not synemmata-like) longer caulocystidia.

Figure 60. 

Mycetinis prasiosmus. Pileipellis structures. Standard bars = 10 µm. UPS-F-740438.

Figure 61. 

Mycetinis prasiosmus. Hymenial structures. A–D Pleurocystidia E–H Basidia. Standard bars = 10 µm. FES 1155 (S).

Figure 62. 

Mycetinis prasiosmus. Hymenial structures. A Basidiole B Immature basidium C Two-sterigmate basidium D–H Mature 4-sterigmate basidia. NOTE: Clam connection on G. Standard bars = 10 µm. UPS-F-740438.

Figure 63. 

Mycetinis prasiosmus. ACaulocystidiaB Basidiospores. Standard bars: A = 10 µm; B = 5 µm. FES 1155 (S).

This treatment includes Mycetinis querceus ss Antonín and Noordeloos (2010). The case for typification and acceptance of Mycetinis prasiosmus is included as Supplementary Data 1.

It might be expected that Noordeloos (2012) followed the nomenclature set out by Antonín and Noordeloos (2010), including Mycetinis querceus as part of the Scandinavia mycota but citing as synonymous “M. prasiosmus (Fr.: Fr.) Fr. ss. auct.” Included was “occasional in temp.-hemib., very rare in southern bore.”

Redhead (1982) reported that stipe cortical tissue (as “pigmented hyphal walls”) of Marasmius copelandii (later re-identified as M. salalis) produced a greenish gray to blue-green pigment in KOH solution. These reactions were also reported for Marasmius olidus and M. prasiosmus. We have been unable to confirm this report in the present study, but if Redhead’s concept of M. prasiosmus followed that of Kauffman (see supplementary data): it is not the European M. prasiosmus. Moreover, later research has proposed M. olidus to accommodate M. prasiosmus ss Kauffman.

Czech Republic, Moravian Karst, Brno-Líšeň, Hádecká planinka,1 Nov. 2001, coll. V. Antonín (as Mycetinis querceus), VA 01.340 (BRNM 666586); Moravia, Lipůvka, Dubová hora, 28 Oct. and 12 Nov. 1960, coll. F. Šmarda s.n. (as Mycetinis querceus) (BRNM 314016). Sweden, Uppland, Uppsala parish, Bondkyrka parish, Eriksberg, forest between Granitvägen and Hågaån, 21.X.1974, coll. S. Ryman (as Marasmius prasiosmus), SR 3241 (UPS-F-740438); Uppland: Uppsala parish, Bondkyrka parish, Kvarnbo lund, 12.XI.1974, coll. Svengunnar Ryman (as Marasmius prasiosmus). SR 3281, (UPS-F-740439); Uppland, Gamla Uppsala Parish, Fullerö backar (3 km N of the church), 13.X.2001, coll. N. Lundqvist (as Marasmius prasiosmus), NL 21502 (UPS-F-740442); Västergötland: Mölndal Parish, Gummebo [N57°30'00", E12°01'00"], 5.X.1940, coll. T. Nathorst-Windahl, No. 2313, Fungi Exsiccati Suecici, Praesertim Upsaliensis [FES as Marasmius prasiosmus), no. 1155 (S, BPI and other presumed distributions; neotype); Västergötland, Vänersborg parish, Botered, X.1860, coll. G. Linnarsson (as Marasmius prasiosmus), s.n. (UPS-F-574708); Västmanland, Västerås-Barkarö parish, Ridön, Munkkällan, 12.X.1986, coll. Herbert Kaufmann (as Marasmius prasiosmus), s.n. (UPS-F-02106).

Canada, British Columbia, Vancouver Island, Gordon Bay, Lake Cowichan, N48°49'35", W124°03'14", 4.X.1979, coll. S.A. Redhead, DAOM 175254 (DAOM).

1) Basidiomata small but robust (pileus 12–16 mm broad; stipe 33–46 × 1–3 mm); 2) spores 15–19 × 3.2–5.1 µm; 3) fruiting habit on fallen leaves of Gaultheria and Berberis; 4) stipe insititious, white upward, brick red downward; distribution from northern California to British Columbia.

Basidiomata (Fig. 64) small but robust. Pileus 12-16 mm wide, convex to plano-convex, somewhat radially furrowed with age to subtly sulcate-striate, moist, translucent-striate, disc “Saccardo’s umber” 5E8, outward “pinkish buff” 6A3 to “pale pinkish buff” 6A2, with paler marginal areas; margin often scalloped; context concolorous, membranous-tough. Lamellae adnate to adnexed, whitish to buff, “tilleul buff” 7B2, moderately spaced and sized, thickish, crenulate and paler on edges, exhibiting necropigment to near “cinnamon buff” 6B4, and characteristically crisped; lamellar edge minutely pruinose to entire, concolorous with lamellar face; lamellulae in 2 tiers. Stipe: 33–46 mm long, 1–3 mm wide, equal or with slightly swollen base, hollow, dry, upward villose to silky, downward sparsely to densely tomentose, becoming hispid with synnemata of stiff, dark caulocystidia up to 1 mm long, apically concolorous with lamellae, downward dark brick, chestnut, “bister” 5F8 to “benzo brown” 9D3 to “fuscous black” 6F4, insititious. Rhizomorphs uncommon, scattered, of two types: 1) resupinate on leaf surfaces, without evidence of origin or termination, 0.6–0.8 mm broad, flattened/strap-shaped, occasionally producing a stellate attachment; and 2) aerial, 3–14 × 0.1–0.3 mm (very slender), unbranched, curly. Odor strong of onion or garlic; taste strongly of onion or sweet garlic.

Figure 64. 

Mycetinis salalis. Photo in natural habitat. Photo courtesy of Steve Trudell. WTU-F 9803.

Scattered on senescent leaves and branches of Gaultheria shallon Pursh and unidentified broad leaves in open forests of Pseudotsuga menziesii and Tsuga heterophylla; northern California to southern British Columbia; Autumn.

Pileipellis constructed of two elements: 1) inflated hyphal termini (Fig. 65E–L), 24–45 × 17–32(-40) µm overall, stalked (stalk 7–18 × 5–7.5 µm), subglobose, utriform, or (usually) with irregular lobose or free-form configurations, firm- to thick-walled (wall -1.5 µm thick, and then sometimes pigmented in yellowish or ochraceous tints; and 2) pileocystidia (Fig. 65A–D) 30–48 × 25–30 overall, stalked (stalk 10–25 × 7–9 µm), firm- to thick-walled (wall -0.7 µm diam, hyaline), distally slightly inflated and beset with thick, digitate or gnarled outgrowths. Pileus and lamellar tramae loosely interwoven; hyphae 5–12 µm diam, clamped, smooth, thin- to firm-walled, nonamyloid. Pleurocystidia (Fig. 66) (32-)37–50 × 5–9 µm, narrowly fusiform to fusiform, conspicuously clamped; contents homogeneous. Basidia (Fig. 67) (32-)41–55 × 8–12 µm, narrowly clavate, often subcapitulate, 4-sterigmate, conspicuously clamped; contents heterogeneous, multiguttulate also with oily inclusions (PhC). Basidiospores (Fig. 69A) (15-)16–18.5(-19) × (3.5-)4–5 µm (Q = 3.00–4.75; Q^m = 3.83; L^m = 16.8 µm), narrowly pip-shipped, clavate to curved-clavate, marasmioid (tapered proximally), thin-walled, inamyloid; contents heterogeneous, multiguttulate. Lamellar edge apparently sterile, lined with cheilocystidia. Cheilocystidia (Fig. 68) (25-)45–84 µm long, stalked [stalk 15–35 × 3–6.5 µm, obscurely clamped, firm- to thick-walled (wall -1.0 µm thick)], somewhat expanded distally (9–14 µm broad), ranging from clavate with no outgrowths to clavate with apical lobose outgrowths to distally branched; branches stout, 5–50 × 2.5–5.5 µm, ascending, often rebranched, rounded at apex. Stipe medullary hyphae 2.5–6.5 µm diam, strictly parallel, tightly packed, free (without slime matrix), thin- to firm-walled, obscurely clamped. Stipe cortical hyphae 3–6.5 µm diam, strictly parallel, free (without slim matrix), firm- to thick-walled (wall -0.7 µm thick, subhyaline), obscurely clamped, immediately turning dull olive (“buffy olive” 3E6, ”yellowish olive”2E5) in 3% KOH solution. Caulocystidia from upper stipe (Fig. 69B) 15->500 × 5–15 µm, supple, subsinuous, thick-walled (wall 0.7–2 µm thick, subhyaline, rarely occluding cell lumen), broadly attached to surface cortical hyphae. Caulocystidia from stipe base 25->1000 × 5–14 µm, erect, stiff, setoid, thick-walled [wall 0.7–2(-4) µm thick, often occluding cell lumen, pigmented pallid yellowish].

Figure 65. 

Mycetinis salalis. Pileipellis elements. A–D, F Pileocystidia E, H Inflated elements without growths G, I–L Inflated elements with free-form, lobose outgrowths. Standard bars = 10 µm. TFB 5724 (TENN 52572).

Figure 66. 

Mycetinis salalis. Pleurocystidia. Standard bars = 10 µm. TFB 5724 (TENN 52572).

Figure 67. 

Mycetinis salalis. Basidia. Standard bars = 10 µm. TFB 5724 (TENN 52572).

Figure 68. 

Mycetinis salalis. Cheilocystidia. A Cluster of cheilocystidia B, C, E–G Individual branched cheilocystidia D Clavate, unornamented element. Standard bars = 10 µm. TFB 5724 (TENN 52572).

Figure 69. 

Mycetinis salalis. A Basidiospores. BCaulocystidia: left from upper stipe, right from lower stipe. Standard bars: A = 5 µm, B = 20 µm. TFB 5724 (TENN 52572).

Desjardin (1987a) and Desjardin and Redhead (1987) reported collections of M. salalis from British Columbia and Washington (apocryphal from Oregon) but not California. A single collection (TFB 8084 = TENN55408) from Trinity Co., California, produced ITS sequence nearly identical to those of My. salalis from farther north, as well as characteristic cheilocystidia, but spores significantly shorter [(10-)12–13(-14) × 3–4 µm (Q = 1.8–4.33; Q^m = 3.36; L^m = 12.3 µm)] then those of My. salalis. TFB 8084 was initially identified as M. copelandii based on spore statistics, but molecular evidence confirmed that it was conspecific or closely related to My. salalis. ITS sequences are presently unavailable for authentic My. copelandii for comparison.

Pleurocystidia in My. salalis, as in other taxa of Mycetinis, are difficult to distinguished from basidioles. Separation has been made on the following characters: 1) consistent narrowly fusiform shape versus consistent subcapitulate-clavate basidiole shape; 2) homogeneous contents (PhC), usually with a single distal dark inclusion, versus multiguttulate heterogeneous contents of basidioles.

Cheilocystidia in My. salalis closely resemble pileocystidia. In neither structure can the branches be termed as setulae, which are considered as significantly smaller in length and breadth. Cheilocystidia of My. salalis resemble pileocystidia of My. scorodonius, but cheilocystidia of the latter are more complex, with ultimate outgrowths shorter and more slender.

Basidiospores of My. salalis are significantly longer than those of My. copelandii. Collection TENN-F-55408-TFB 8084 (morphologically My. copelandii) is characterized by appropriately shorter spores but its ITS sequence is essentially congruent to those of My. salalis (0.2% divergence from My. salalis collections DAOM175251 and WTU9803; Fig. 2). This collection, therefore, appears enigmatic. The situation may be resolved when additional ITS sequences become available for My. copelandii and/or when multigene trees can be produced.

Redhead (1982): “The change to greenish grey of the pigmented hyphal walls and the blue green plaque in KOH is reminiscent of such reactions in Collybia species allied to C. alkalivirens Singer (see Halling. Mycotaxon 8: 453-458. 1979). These reactions also occur in Marasmius, Mycetinis olidus and Marasmius, Mycetinis prasiosmus.”

United States, California, Trinity Co., Rte 299, Grey’s Point Campground, N40°56'55", W123°53'47", 15.XI.1996, coll RHP, det. D. Largent (as M. copelandii), TFB 8084 (TENN55408). Washington, King Co., vic. Greenwater, Federation Forest State Park, N47°09'20.21", W121°42'10.98", 3.X.1992, coll RHP, TFB 5724 (TENN52572); Mason Co., Shelton, Shelton Point, N47°13'05", W123°06'58", 25.X.1966, det. K. Harrison (as Marasmius scorodonius), Stz 13741 (WTU-F-9219); Pierce Co., Mount Rainier National Park, Hwy 123, 3.3 miles south of 123/410 junction, N46°49'28.96", W121°32'41.75", 5.X.1997, coll & det S. Trudell (as Mi. perforans), Trudell 97-278-17 (WTU-F-009308); Whatcom Co., vic. Bellingham, Silver Lake area, N48°58'16.8", W122°04'05.2", 10.X.1992, coll Coleman McCleneghan, TFB 5822 (TENN52249).

(neotype, design. Antonín and Noordeloos 1993). Fungi Exsic. Scandinavia, no. 1 (Sweden, Stockholm, Autumn, 1889, coll. A. Romell (BR; isoneotypes B, BP, W).

1) Basidiomata of moderate size (pileus 10–30 mm broad; stipe 40–60 × 0.5–1.3 mm); 2) stipe brown or orange brown upward, midsection off-white, downward mahogany to red-brown, glabrous; 3) pileipellis at pileus margin with inflated hyphal termini and broom cell-like cells; 4) spores ellipsoid to amygdaliform, L^m = 9.0 µm; 5) strong garlic odor and taste; 6) distribution in Europe and North America (rare on North American west coast).

Basidiomata (Fig. 70) of moderate size. Pileus (3-)10–30 mm broad, almost hemispherical when young, convex with slightly raised disc, then convex to almost applanate, even to slightly depressed on disc, smooth, glabrous to subglabrous, hygrophanous; disc neutral brown, “sayal brown” 6C5, “cinnamon” 6B5, brownish orange 6C4, when moist brown, yellow-brown or ochre, sometimes paler towards margin; margin slightly involute then more or less straight, undulating, distinctly pallescent on drying to pale brown 6D5, pale ochraceous, “pale ochraceous buff” 4A2, “pale pinkish cinnamon” 6A2, pinkish, “pinkish buff” 6A3, or dirty white, smooth or slightly radially rugulose, even subsulcate when old. Lamellae adnexed to adnate to a thin pseudocollarium which becomes most visible with lamellar secession in drying, subdistant, close to crowded, total lamellae 38–48, through lamellae 15–20 (in robust form total lamellae 72–97, through lamellae 27–32), slightly intervenose when old, narrow (lamellae -1.5 mm broad); white to orange white 5A2, near “pale ochraceous buff” 4A2, “pale pinkish cinnamon” 6A2 to off-white when fresh; frequent necropigment upon drying and storage to dusky cantaloupe color with a hint of pink to make “light ochraceous buff” 5A4 to “pinkish buff” 6A3; lamellulae in at least two ranks, often rudimentary; lamellar edge concolorous with lamellar face, minutely pruinose. Stipe (15-)40–60 × 0.5–1.5(-3) mm, terete to slightly compressed, often slightly broadened apically, sometimes tapering gradually downward, hollow, often appearing insititious, but usually with poorly developed basal disc or basal mycelium, glabrous to sometimes delicately pruinose at apex only, pallid to pale brown at apex, “tilleul buff” 7B2, drying to “cinnamon buff” 6B4, brownish orange 6C4, downward off-white becoming brown, “sayal brown” 6C5, dark reddish brown 7F8, mahogany, “Verona brown” 6E5, or orange-brown, “Brussels brown”6E6, “Mikado brown” 7C6, “mummy brown” 6F8 towards base, with fine rusty tomentum at base. Context thin, white to pale brown. Rhizomorphs not reported. Odor weak to strong of garlic, rarely lacking; taste usually alliaceous.

Figure 70. 

Mycetinis scorodonius. Basidiomata. Standard bars = 20 mm. A Courtesy Acta Fungorum B Courtesy P.N. Urkiola.

Clustered to gregarious, not fastidious of substratum for fruiting, coniferous needles, various dead deciduous leaves from forest trees (Fagus, Quercus, Alnus, Acer, etc.) and heaths; widely distributed through Europe including western Russia, Scandinavia, northern Africa and eastern North America (see Antonín and Noordeloos 2010), reported as rare in California; Autumn.

Pileipellis at pileus margin a mixture of three major structures: 1) roughly hymeniform layer of inflated cells (Figs 71A–D, 72A–F) (16-)33–40(-45) × 14–23 µm overall, thick-walled (wall -1.5 µm thick, hyaline, smooth or minutely roughened, stalked (stalk 7–20 × 3.5–5.5 µm), clamped; 2) similar inflated termini, overall 33–47 × 14–33 µm overall, stalked (stalk 12–18 × 3.5–6 µm, clamped), usually expanded distally and then beset by complex lobate to diverticulate processes (Fig. 72G–J); diverticula papillate, fin-like, lobate to digitate, -9 µm long, subrefringent (PhC); and 3) differentiated broom cell-like pileocystidia (Fig. 72E–L) 21–28 × 8–16 µm overall, stalked (stalk 3–8 × 3.5–5.5 µm), somewhat swollen distally, thick-walled throughout, surmounted by a cluster of outgrowths; outgrowths digitate to catenulate, hyper-refringent (PhC), often knobbed at apex, occasionally dichotomous. Pileipellis over pileus disc constructed of two hyphal types: 1) a coarse hymeniform layer composed of clavate, pyriform, utriform, vesiculose, sometimes slightly fusiform or lobate elements, (5.0-)20–42(-58) × 13–24(-35) µm, smooth or less frequently with a few digitate apical projections (not true broom cells) up to 6 µm long, or only somewhat apically roughened, thin- to thick-walled (wall up to 1.5–2.0 µm, hyaline to yellow-brown); and 2) free-form hyphal termini, coarsely complexly lobed, stalked (stalk 5–12 × 4–6 µm), overall 15–30 × 17–40 µm; individual lobes and hyphae 5–8.5 µm diam, thin- to firm-walled; contents heterogeneous. Pileus and lamellar tramae loosely interwoven; hyphae of two types: 1) 3–7.5 µm diam, firm-walled, conspicuously clamped; and 2) 3.5–9 µm diam, thin- to firm-walled, conspicuously clamped; contents heterogeneous. Pleurocystidia (Fig. 73) 31–40 × 5–7 µm, cylindrical to narrowly fusiform, acutely rounded at apex, conspicuously clamped; contents more or less homogeneous. Subhymenial hyphae branched, cylindrical, hyaline, 2.0–5.0 µm wide, clamped. Basidioles clavate, cylindrical to subampulliform, obscurely clamped; basidia (Fig. 74) 28–42 × 7.0–9.0 µm, clavate to subcapitulate, (2-)4-sterigmate, obscurely clamped; contents heterogeneous, multiguttulate. Basidiospores (Fig. 75) (6.5-)8.0–10.0(-11.0) × (3.5-)4–4.5(-5.5) µm (Q = 1.55–2.57; Q^m = 1.93; L^m = 9.0 µm), ellipsoid, ovate to amygdaliform, smooth, thin-walled, inamyloid; contents heterogeneous, minutely multiguttulate. Cheilocystidia (Fig. 76) locally plentiful, siccus-type, (12-)23–40 × 14–21 µm overall, staked (stalk 12–24 × 3–5.5 µm, obscurely clamped), often inflated distally, surmounted with a complex of diverticula; diverticula 2–10 × 1–1.5 µm, gnarled, often dichotomous. Stipitipellis a cutis of 3.0–12.0 µm wide, cylindrical hyphae with yellow-brown to dark brown, slightly thickened (-2.0 µm) walls. Caulocystidia not differentiated, but sometimes scattered, cylindrical, terminal endings of cortex hyphae present.

Figure 71. 

Mycetinis scorodonius. Pileus margin pileipellis elements. A–D Inflated elements E–L Broom cell-like elements. Standard bar = 20 mm. TFB 14229 (TENN-F- 68086).

Figure 72. 

Mycetinis scorodonius. Inflated pileipellis elements. A–F Structures without outgrowths G–J Structures with digitate to lobate outgrowths. Standard bars = 10 µm. TFB 13746 (TENN-F- 65123).

Figure 73. 

Mycetinis scorodonius. Pleurocystidia. Standard bars = 10 µm. TFB 7261 (TENN-F-53568).

Figure 74. 

Mycetinis scorodonius. Basidia. Standard bars = 10 µm. TFB 7261 (TENN-F-53568).

Figure 75. 

Mycetinis scorodonius. Basidiospores. Standard bar = 5 µm. TFB 7261 (TENN-F- 53568)

Figure 76. 

Mycetinis scorodonius. Cheilocystidia. Standard bars = 10 µm. TFB 7261 (TENN-F-53568).

Description of pleurocystidia may be somewhat miscast. Traditionally, pleurocystidia and basidioles have been confused. The description above is based on the following circumstances: 1) more acutely rounded pleurocystidial apex than subcapitulate basidioles; 2) homogeneous pleurocystidial contents as compared with the heterogeneous contents of basidia and maturing basidioles; and 3) usual length of both structures not acceding that of basidia.

The marasmioid cheilocystidia were sought in three European collections (Belgium, Netherlands, Sweden) in at least two different mounts from two different basidiomata of each collection, so the sudden abundance of highly differentiated cheilocystidia in TFB 7261 was surprising. Moreover, the entire lamellar edge was covered and so was sterile. In other lamellar margins, only structures resembling the clavate shapes found in other species of Mycetinis were observed.

Mycetinis scorodonius may exist in two forms: 1) pileus -20 mm broad; 2) lamellae distant, narrow; 3) stipe slender (1–2.5 mm broad, terete), tapering downward; versus 1) pileus 15–32 mm broad; 2) lamellae crowded, well-developed; 3) stipe robust (2–4 mm broad, often compressed). These forms share the following: 1) strong odor and taste of garlic when fresh; 2) smooth pileus with brown disc and tan limb; 3) pileocystidia in pileipellis from pileus margin. To this writing (X.2016), the robust form has been seen from Belgium, Samara Region, Russia and North America; the slender form has been limited to the Leningrad Region, Russia.

There were sufficient ITS sequences to analyze population structure in Mycetinis scorodonius (Fig. 77). European and North American populations are not mutually exclusive. There is a distinct North American haplotype but European collections seem to be a mix of two haplotypes; one, a North American-like haplotype and one not found in North America termed “European-like” in Fig. 77. A single North American collection has the European-like haplotype and a collection from Mexico is heterozygous for both European-like and North American-like haplotypes.

Figure 77. 

Mycetinis scorodonius. Unrooted PhyML of My. scorodonius collections based on the ribosomal ITS region.

The origin of the two European haplotypes is uncertain but it would appear that some gene flow between Europe and North America has occurred, either by long distance spore dispersal or human mediation.

Gordon (1994) and Gordon and Petersen (1998) employed three methods in a taxonomic analysis of numerous pan-Atlantic collections of My (as Marasmius) scorodonius. Using basidiome collections and derived cultures of European and eastern North American specimens, collections were submitted to Numerical Taxonomy and Multivariate Analysis System (NTSYS-pc; (Rohlf 1992)) and UPGMA cluster analysis, pairing experiments using single-basidiospore isolates and laccase electrophoresis. Although some micromorphological variation was found (i.e. presence/absence of cheilocystidia), European and North American collections were intermixed, with no clear-cut separation detected. Likewise, pairing experiments indicated that European and eastern North American collections were sexually intercompatible, indicating a single biological taxon across the trans-Atlantic barrier. Laccase electrophoresis, however, clearly separated European versus eastern North American collections, indicating lack of long-distance genetic exchange across the oceanic barrier. Altogether, results were not incompatible with conclusions shown here by use of DNA sequences.

Although apparently rare, one specimen of My. scorodonius from Washington (state) has been examined. Another from California is reported in Mycoportal (Humboldt Co., Patrick’s Point State Park, 25.IX.1968, coll. & det. HD Thiers, annot. DE Desjardin, SFSU-025263).

Basidiomata of My. alliaceus and My. copelandii do not exhibit differentiated pileocystidia. In My. copelandii, free-form cells accompany inflated hyphal termini, but in My. alliaceus, the inflated elements are the only element observed, although at pileus margin some individuals are found to produce apical outgrowths.

Belgium, Dimpre, vic. Heer, Massembre, N50°09.360", E4°51.224", coll. KWH, TFB 13746 (TENN65123). Canada, Nova Scotia, Kejimkujik National Park, N44°22'44", W65°20'32", Rogers Brook Trail, 4.VIII.1992, coll SA Gordon, TFB 5031 (TENN51442); Kejimkujik Nat. Park, Grafton Lake Loop Trail, N44°22'55", W65°10'55", coll. SA Gordon, TFB 5038 (TENN-F- 53468). The Netherlands, Gelderland Prov., Wageningen, N51°58'12", E5°39'54", 3.VIII.1959, leg. K. Bakker, det. C. Bas, LRH 23881 (TENN-F-23881). Russia, Leningrad Region, Dist. Lindylovskaye, Rocha Reserve, N60°14.30', E29°32.394', 25.VIII.1999, coll RHP, TFB 10400 (TENN58260); Samara Region, Zhijulevsky Reserve, vic. St. Nicholas Spring, Shirayevo Valley, N53°23.425', E49°57.939', 17.VIII.2004, coll RHP, TFB 12168 (TENN-F-60107). Sweden, Uppland, vic. Uppsala, Tärnby Lund, N59°51'345", E17°38'05", 4.IX.1994, coll RHP, TFB 7261 (TENN-F-53568); Västergötland, Lillaedet, Myrtuvan, N58°08'30", E012°02'40", 19.IX.1991, coll/ SA Gordon et al., TFB 3796 (TENN-F-50533). United States, Georgia, Rabun Co., Rte 28, approx. 1 mi into GA, N34°57'11.32", W83°11'00.70", 1.VI.1993, coll RHP (as M. copelandii var. olidus), TFB 6213 (TENN52873); Maine, Hancock Co., Lamoine, N44°29'22", W68°18'35", 25.VII.1992, coll. SA Gordon & W. Litten, TFB 5005 (TENN-F-53474); Massachusetts, Berkshire Co., vic. North Adams, N42°42'03", W73°06'33", 16.IV.1986, coll. DE Desjardin, DED 4060 (TENN-F- 54179); Michigan, Marquette Co., Powell, vic. Ives Lake, N46°50'47", W87°50'05", 28.VIII.1971, coll. RHP, TENN-F-036156; North Carolina, Macon Co., vic. Highlands, Nantahala Nat. For., Blue Valley, Pickelsimer’s Falls Trail, N35°00'50", W83°14'39", 18.VII.1991, coll. SA Gordon., TFB 3701 (TENN-F- 50689); Tennessee, Blount Co., GSMNP, Cades Cove, Parsons Branch Rd., N35°33'44", W83°22'48", 14.IX.1987, coll DE Desjardin, DED4500 (TENBN-F-54182); GSMNP, Cades Cove, vic. Oliver cabin, N35°36'25.42", W83°47'39.03", 12.VI.2013, coll. RHP, TFB 14229 (TENN68086); Sevier Co., GSMNP, Greenbrier area, N35°42'28", W83°22'48", 19.VII.1986, coll. DE Desjardin, DED 3875 (TENN-F- 54209); GSMNP, Mt. LeConte, N35°39'18", W83°26'28", 4.VI.1957, coll. LR Hesler, TENN-F-009183. Washington, King Co., Seattle, Univ. Washington campus, N47°39'14.83", W122°18'28.53", 12.X.1942, coll. & det. DE Stuntz, STz 1239 (WTU-F-9221).

United States, Washington, King Co., Bellevue, N47°34'55.91", W122°10'06.96", 4.XI.2015, coll. K. Dyson, KLD 2220-11-4-2015 (TENN69345),

1) Basidiomata diminutive (pileus 3–10 mm broad; stipe 10–33 × 0.8–1.5 mm); 2) stipe glabrous-shining, not at all vestured; 3) pileipellis at pileus margin a combination of thick-walled inflated elements and arbuscular pileocystidia; 4) pileipellis over pileus disc a hymeniform layer of inflated hyphal termini, mostly thick-walled and hyaline, with scattered thicker-walled, pigmented individuals; 5) spores 8–9.5 × 3.5–4.5 µm (L^m = 8.65 µm); 6) fruiting on soil or minute plant detritus in urban environments.

Basidiomata (Fig. 78) diminutive, sparsely gregarious, often cespitose in small groups. Pileus 3–10 mm broad, strongly convex when young with strongly inturned margin, becoming shallowly convex to almost plane by maturity, sometimes shallowly and broadly umbonate, smooth, suede-like (not glabrous), near “sayal brown” 6C5, “cinnamon” 6B5 to “drab” 6D3 over disc, somewhat paler, “ochraceous buff” 5A5, “light grayish olive” 30B2, “tilleul buff” 7B2, “pale pinkish cinnamon” 6A2, over limb and margin, often somewhat radially puckered; margin inrolled when immature, downturned to gently downturned by maturity, entire with no evidence of striation. Lamellae adnexed to adnate, attached to a weak pseudocollarium not seceding with dried lamellae, well-developed (-1 mm broad), hardly ventricose, thickish, total lamellae 52–56, through lamellae 17–22, characteristically crisped when dried, probably off-white when fresh, “cartridge buff” 30A2 to “light buff” 3A2 when dried; lamellulae in 1–2 ranks. Stipe 10–33 × 0.8–1.5 mm, terete, more to less equal, gradually enlarged downward from midsection to base, insititious, glabrous-shining, not at all vestured, apically near “tawny olive” 5C5, downward in midsection “ochraceous tawny” 6C6, downward to base “mummy brown”6F8 to “bister” 5F8. Odor strong, of garlic, but perhaps not all populations; taste not recorded.

Figure 78. 

Mycetinis scorodonius f. diminutivus. Basidiomata. A 22200-11-4-2015 B 10961-10-20-2015 C 22167-10-14-2015 D Reconstruction from dried specimen. Standard bars: A–C = 10 mm; D = 20 mm. A–C courtesy K. Dyson.

Habitat and phenology Fruiting substrate soil with most common over-story trees Pseudotsuga and/or Thuja, probably mulch or minute woody debris; Fall; at this time known only from four collections from urban sites, King Co., Washington.

Pileipellis complex, differing significantly between pileus margin and pileus disc; pileal hairs not observed. Pileipellis of pileus margin a mixture of two elements: 1) inflated elements (Fig. 79A–D) 12–27 × 7–11 µm overall, with stalk absent to 4–7 × 4–5.5 µm, obscurely clamped, thick-walled (wall -0.8 µm thick, hyaline), delicately roughened, usually producing diverticula apically; diverticula 2–6 × 1–1.5 µm, ranging from bud-like to digitate, usually gnarled and often dichotomous, semi-refringent; and 2) pileocystidia (Fig. 79E–H) 23–37 ×10–14 µm overall, arbuscular, stalked (stalk 7–18 × 3–5.5 µm, obscurely clamped), producing a complex of diverticula; diverticula 2–8 × 1.5–2.5 µm, gnarled, often dichotomous, refringent. Pileipellis of pileus disc a mixture of two elements: 1) inflated hyphal termini (Fig. 79E–H), subglobose, often coarsely dichotomously lobed, thick-walled, smooth or delicately roughened, hyaline, obscurely clamped; and 2) inflated hyphal termini (Fig. 80A–D), significantly thick-walled (wall -2.0 µm thick along flanks, up to 3 µm thick distally, pigmented yellowish (PhC), smooth; contents dense, pigmented dull ochraceous. Pileus trama loosely interwoven; hyphae 3–7.5(-14) µm diam, firm-walled, often swollen somewhat near branch points, conspicuously clamped. Pleurocystidia (Fig. 81) 29–42 × 7–9 µm, fusiform with acutely rounded apex, conspicuously clamped; contents more or less homogeneous. Basidioles clavate; basidia (Fig. 82) 35–40 × 8–10 µm, elongate-clavate, 4-sterigmate, conspicuously clamped; contents heterogeneous, appearing oily. Basidiospores (Fig. 83) (7.5-)8–9.5(-10) × 3.5–4.5(-5) µm (Q = 1.89–2.29; Q^m = 2.12; L^m = 8.65 µm), ellipsoid to narrowly subamygdaliform, hyaline, thin-walled, inamyloid; contents heterogeneous, multigranular or multiguttulate. Lamellar edge probably sterile; cheilocystidia (Fig. 84) plentiful, 23–35 × 6.5–11 µm overall, stalked (stalk 8–20 × 3.5–4.5 µm, obscurely clamped), swollen distally, thick-walled (wall -0.7 µm thick, hyaline), surmounted by a cluster of diverticula; diverticula stiff, rigid, gnarled, often branching, usually dichotomously. Stipe medullary hyphae 3.5–8.5 µm diam, firm- to thick-walled (wall -0.5 µm thick, hyaline), strictly parallel, free (not involved in slime matrix), conspicuously clamped. Stipe cortical hyphae 2–5.5 µm diam, thick-walled (wall -1.0 µm thick, weakly pigmented), obscurely clamped. Caulocystidia absent.

Figure 79. 

Mycetinis scorodonius f. diminutivus. Pileipellis elements from pileus margin. A–D Thick-walled, inflated elements with diverticula E–H Arbuscular pileocystidia. Outlines furnished to better interpret photographs. Standard bars = 10 µm. WTU 19061-10-20-2015.

Figure 80. 

Mycetinis scorodonius f. diminutivus. Pileipellis elements from pileus disc. A–D Thick-walled, pigmented elements E–H Thick-walled, hyaline elements. Outlines furnished to better interpret photographs. Standard bars = 10 µm. WTU 19061-10-20-2015.

Figure 81. 

Mycetinis scorodonius f. diminutivus. Pleurocystidia. Standard bars = 10 µm. WTU 10961-10-20-2015.

Figure 82. 

Mycetinis scorodonius f. diminutivus. Basidia. Standard bars = 10 µm. WTU 19061-10-20-2015.

Figure 83. 

Mycetinis scorodonius f. diminutivus. Basidiospores. Standard bar = 5 µm. WTU 19061-10-20-2015.

Figure 84. 

Mycetinis scorodonius f. diminutivus. Cheilocystidia. A Lamellar edge B, C Individuals with rudimentary diverticula D–I Individuals with typical diverticula. Standard bars = 10 µm. WTU 10961-10-20-2015.

Pileipellis in My. scorodonius f. diminutivus is complex. Elements of pileus margin differ substantially from those of the pilus disc. This complexity is similar to that seen in My. opacus and My. scorodonius, both of which form pileocystidia at or near the pileus margin, and suppress them over the pileus disc. The occasional occurrence of very thick-walled, pigmented inflated individuals in the pileus disc is typical of the genus.

A non-vestured stipe is not typical of Mycetinis taxa. Mycetinis cinnamomeus from South Australia exhibits basidiomata of similar size; Cleland’s description does not include vesture and Desjardin’s notes on the type specimen indicates absence of caulocystidia. Mycetinis scorodonius also exhibits a glabrous-shining stipe, which may be reflected in ITS sequences from f. diminutivus, also without stipe vesture, which match those of My. scorodonius. Basidiomatal dimensions are significantly different, however, raising the question of molecular versus morphological evidence. This situation also arises with My. salalis/My. copelandii (q.v.).

All listed collections of f. diminutivus were made in mulched planters near office buildings, from which plant debris was regularly removed. Paucity of substrate, perhaps exacerbated by urban environment (i.e. lack of water, aerial pollution, frequent harsh sunlight, mulch pH, etc.) may be causative factors in the production of diminutive basidiomata.

United States, Washington, King Co., Bellevue, N47°34'55.91", W122°10'06.96", 4.XI.2015, coll. K. Dyson, KLD 2220-11-4-2015 (TENN69345 (holotype); same data, KLD 22218-11-4-2015 (TENN69348); same location, 14.X.2015, coll. K.L. Dyson, KLD 22167-10-14-2015 (TENN69347); Redmond, N47°37'56.04", W122°07'59.56", 20.X.2015, coll. K.L. Dyson, KLD 19061-10-20-2015 (TENN69346).

Austria, Tirol, Obergurgl, N46°52'13", E11°01'37", 28.VIII.2006, coll. P.-A. Moreau, no. 05082708 (LIP, isotype ZT).

1) Basidiomata diminutive (pileus 3-10 mm broad; stipe 20–30 × 0.5–1 mm); 2) associated with Rhododendron ferrugineum twigs and leaf litter; 3) strong odor of garlic from fresh material but dissipating in drying; 4) adult pileus pallid rosy, shallowly sulcate-striate; 5) spores 9.5–11.8 × 5–6.2 µm, subamygdaliform, somewhat tapered proximally; 6) stipe subinsititious or minutely wooly at base.

The following description is a translation and rearrangement of the protolog description by Moreau (2007).

Basidiomata diminutive. Pileus 3–10 mm broad, strongly convex when young becoming convex, often subtly broadly umbonate, eventually plane to everted, weakly subhygrophanous, smooth, a little glistening, entirely dark reddish in very juvenile specimens, becoming brown-red, rapidly paling to dull ochraceous yellow with age, with central umbo remaining dark reddish, uniformly brownish when dried; margin entire to shallowly sulcate-striate, paler than disc. Lamellae distant, thickish, ventricose, adnate, attached to a loose or clasping pseudocollarium, total lamellae 20–28, through lamellae 10–12, whitish then pale cream in age, with scattered dark reddish punctations; lamellulae in 1(-2) ranks. Spores deposit not obtained. Stipe 20–30 × 0.5–1 mm, terete, equal, insititious to subinsitititious, flocculose at apex and occasionally to midsection, somber reddish when young, in age assuming an ochre shade, yellow-red mycelium apparent on the stipe apex. Rhizomorphs not visible. Flesh pliant, reviving. Odor very powerful of garlic (Allium sativum), dissipating on drying but regenerating on rehydration; taste alliaceous, sweet.

Known from only few specimens; apparently associated with dead twigs, leaves and litter of Rhododendron ferrugineum; approximately tree-line in Rhododendron belt in mountains of central Europe (Austria, France, Switzerland); mid-summer.

Pileipellis an irregular hymeniform layer about 80 µm thick, of hyphal termini 18–55 × 6–22 µm, arising from subterminal elements, irregularly clavate to obpyriform, thin- to thick-walled (wall -1 µm thick, yellow brown), entire to mostly forming digitate diverticula, mixed with shorter, non-emergent, cylindrical articles; diverticula 3–6 µm long. Hypodermium filamentous, hardly differentiated, of slender hyphae (2–4 µm diam), smooth or with pigment incrustation in hardly separable scabs. Pileus trama dextrinoid, of mixed hyphae, more regular in hypolamella, with slender cylindrical hyphae (-3.5–10 µm diam), smooth or with various granular pigment deposits here and there. Lamellar trama regular, dextrinoid, of slender, clamped hyphae (3–3.5 µm diam), parallel, hyaline. Subhymenium filamentous, dense, arranged in a layer. Pleurocystidia fusiform, with attenuate apex before maturity, clamped (see illustration with basidia; Moreau 2007). Basidioles clavate, clamped; basidia 38–45 × 8.5–9.5 µm, cylindro-clavate, (2-)4-sterigmate, clamped; sterigmata short. Basidiospores (9.0)9.5–11.8(12) × 5.0–6.2 µm [Q = (1.60)1.75–2.03(2.20)], fusiform-amygdaliform to subcylindrical, generally more or less obtuse distally, smooth, non-dextrinoid, not cyanophilous; contents often with a large central guttule. Lamellar edge sterile; cheilocystidia 22–40 × 6–10 µm, numerous but short and hardly emergent, cylindrical, lobed with irregularly digitate diverticula, mixed with clavate basidioles with yellowish content. Stipe cortex of slender hyphae (3–5 µm diam), with fine, yellow, strongly localized incrustations; medulla dextrinoid; caulocystidia, 18–80 × 4–11 µm, hyaline, gnarled, cylindrical or clavate, isolated or in compact bouquets.

Moreau (2007) compared M. subalpinus to M. kallioneus and M. scorodonius var. virgultorum (here at species rank), now accepted as members of Mycetinis, and suggested (pers. comm.) such a transfer for M. subalpinus. The coarsely hymeniform pileipellis of M. subalpinus, composed of inflated, thick-walled hyphal termini and broom cell-like, branched pileocystidia, is also typical of Mycetinis. Macroscopically, basidiome size and stature, with reddish coloration, thick, ventricose lamellae attached to a clasping pseudocollarium also point toward Mycetinis. Association with Rhododendron is similar to substrate preference of M. opacus, which also exhibits branched pileocystidia, but similarities end with these limited characters. Basidiomatal size and stature are reminiscent of My. curraniae, My. olidus and My. cinnamomeus.

Morocco, herb. Malençon, no. 5663, Institute Montpelier (MPU) [material unavailable].

1) Basidiomata diminutive (pileus 3.5–8 mm broad; stipe 7–18 × 0.4–0.5 mm), marasmielloid; 2) distribution trans-Mediterranean; 3) fruiting on canes of Rubus and other deciduous detritus; 4) stipe vestured overall or at least upward; 5) stipe pale upward, downward brown-red; 6) spores 7–8 × 3.6–4.3 µm.

The following description is a combination and rearrangement of descriptions by Malençon and Bertault (1975), Eyssartier and Moreau (2001), and Antonín and Noordeloos (2010).

Basidiomata (Fig. 85A) diminutive, marasmielloid. Pileus 3.5-8 mm broad, hemispherical when young and then subumbonate, becoming convex then applanate, in age usually applanate to everted, not hygrophanous, drying uniformly, thin and supple, dry, sometimes subrugulose, obscurely bruised over disc, pruinose and finely powdery or minutely saccharine-granular; disc reddish alutaceous, between ferrugineous and fulvous (Saccardo, Chromotaxia), dark reddish (Eyssartier and Moreau 2001); margin involute when young, then downturned, entire, sometimes visibly striate in age, paler than disc to off-white, perhaps with weak pinkish tint (“beige-carné” teste Eyssartier and Moreau 2001). Lamellae adnexed to nearly free (broadly adnate to emarginated (teste Antonín 1995), -1.5 mm broad, moderately close to distant, total lamellae 12–15 (19–22 test Antonín (1995); 20–24 teste Eyssartier and Moreau 2001), through lamellae 4–6 (two teste Antonín 1995), acute toward pileus margin, enlarged and sinuate near attachment, white to cream-colored on face, rosy cream on sinus, in rugulose ridges, finally interveined or reticulate in age; lamellar edge concolorous, pubescent (teste Antonín 1995); lamellulae in one rank (teste Eyssartier and Moreau 2001). Spores white. Stipe (4-)7–18(-25) × 0.3–0.5(-1) mm, slender, terete, equal through its major part although dilated under the lamellae and sometimes subbulbous at base, erect or ascendant, rigid, insititious (teste Antonín 1995) hollow when adult, a little pruinose at apex, downward smooth or hairy (entirely furfuraceous-squamulose, strigose at base, teste Antonín 1995) (“avec seulement quelque courts trichoïdes bruns àla base” teste Eyssartier and Moreau 2001), cream colored at apex, amber and darker to brown-red downward (“rouge-purpurin sombre” teste Eyssartier and Moreau 2001). Flesh thin, white or weakly tinted under the union to stipe or apex of stipe, rosy at its base. Odor of garlic, perceived in nature even before the basidiomata; taste similar (teste Antonín 1995).

Figure 85. 

Mycetinis virgultorum. A Basidiomata B Pileipellis structures C Cheilocystidia D Basidiospores. Standard bars: B–D = 10 µm; A = not to scale; smaller basidiomata circ. 2×, basidiome at right circ. 5×. Adopted from Malençon & Bertault, 1975.

Fruiting on canes of Rubus discolor, decaying deciduous leaves and twigs, including Quercus coccifera, Vibernum, Erica; distribution (see Antonín 1995; Antonín and Noordeloos 2010; Eyssartier and Moreau 2001) trans-Mediterranean Sea, as far north as France (Bon 1994); March, June, October, November, December.

Pileipellis (Fig. 85B) composed of a coarse hymeniform layer of hyphal termini of two types: 1) about 20–30(-40) × (7-)10–15(-40) µm, clavate, broadly clavate to obpyriform,, firm- to thick-walled (wall <1 µm thick), sometimes pigmented brownish (teste Antonín 1995); and 2) firm-walled, deformed or arbuscularly branched with irregular digitate protuberances. Pileus flesh interwoven, lacunose, composed of filamentous hyphae 3.5–8 µm diam, branched, clamped, secondarily septate, often encrusted with plaques and/or zebroid deposits. Pleurocystidia probably present, fusiform (see illustration of basidioles by Eyssartier and Moreau 2001). Basidioles cylindrical to narrowly clavate; basidia 23–31 × 5–7 µm, cylindro-clvate, 4-sterigmate, clamped at base; sterigmata more than 3 µm long. Basidiospores (Fig. 85D) 7–8 × 3.6–4.3 µm, ellipsoid to subnavicular to a base with small, oblique apiculus, hyaline, thin-walled, inamyloid. Lamellar edge sterile; cheilocystidia (Fig. 85C) 15–30 × 6.2–9.2 µm (teste Antonín 1995), hyaline, clavate to subglobose, surmounted by coarse, mostly digitate or coralloid diverticula. Stipe medullary hyphae 10–13 µm diam, strictly parallel, firm- to thick-walled (wall -2.5 µm thick), resembling large fibers, which cover the bottom of the stipe. Stipe cortical hyphae 3–4(-6.5) µm diam, thick-walled (wall -1.5 µm thick, pigmented). Caulocystidia (teste Antonín 1995) in scattered bundles of (sub)erect, cylindrical hyphae present on stipe surface.

The description above is adopted from those cited herein. Although the abbreviated translation of Malençon's and Bertault (1975) description presents an outline of characters, descriptions of other characters are missing: 1) stipe seems to be smooth, without caulocystidia, although caulocystidia are reported by others; 2) stipe insertion is illustrated as insititious but not described as such; 3) pleurocystidia are reported as absent, but “basidioles” are reported as clavate or fusoid, and the fusoid structures are probably pleurocystidia. Antonín (1995), based on a specimen from Italy, and Eyssartier and Moreau (2001) offered more complete descriptions, but still without recognition of pleurocystidia.

Antonín’s (1995) report of spore dimensions: (5.8-)6.3–7.7 × 3.1–3.8 µm [E = 1.8–2.0(-2.3), Q = 2.0]. Spore measurements by Eyssartier and Moreau (2001): 6.5–7.5 × 3–4(4.5) µm.

Malençon and Bertault (1975) had opportunity to see M. scorodonius, which also produced a strong garlic odor, and concluded that their organism was a dwarf state. Simultaneously, however, their basidiomata resembled more closely those of M. (Ma.) ramealis, differing in pileipellis characters.

A parallel situation of basidiomatal size concerns My. copelandii var. olidus, in which basidiomatal size, fruiting substrate and distribution of the variety all differ from its parent species. My. olidus is here proposed at species rank. Likewise, in light of basidiome size throughout Mycetinis, which seems to sort into two categories, it is difficult to treat My. virgultorum as a variety under My. scorodonius, so it is here proposed at species rank.

Desjardin and Horak (1997) mentioned similarities between M. curraniae and M. scorodonius var. virgultorum. The two would seem to exhibit similar morphological characteristics, but fruiting substrate and a circum-Mediterranean distribution would seem exclusive to the Antipodal fungus. Perhaps comparison should be made also with My. cinnamomeus from South Australia. When molecular data on My. virgultorum become available, this situation may be elucidated.

China, Yunnan Prov., Simao Pref., vic. Simao, “Red Flag Preserve,” N22°47'23", E100°58'33", 4.VIII.1990, coll. RHP, Wu Qiu-xin, Li, TFB 3103a (TENN-F-49172)

Yunnanensis; referring to Yunnan Province, China, where all known collections were found.

1) Diminutive basidiomata (pileus 3-8 mm broad; stipe 10–17 × 0.3–0.8 mm); 2) white to off-white, convex pileus; 3) vestured stipe; 4) spores 6–9.5 × 3–4 µm (L^m = 7.3 µm); 5) habitat on dead sclerophylllous leaves; 6) distribution in southwestern China.

Basidiomata (Fig. 86A, B, D) diminutive, loosely gregarious on midribs of subsclerophyllous leaves. Pileus 3–8 mm broad, convex to shallowly convex, smooth, dull, not glabrous (perhaps suede-like), white to off-white when fresh, with disc slightly pallid grey, when dried becoming ochraceous orange; margin somewhat scalloped, shallowly sulcate, downturned. Lamellae (Fig. 86C) distant, adnexed, seceding on drying, not well-developed (<1 mm broad), thickish, not anastomosing or forked, total lamellae 26–29, through lamellae 8–13, with a few rudimentary lamellulae in one rank, white when fresh, drying to near “ochraceous buff” 5A5; lamellar edge minutely fimbriate, paler than lamellar face. Stipe 10–17 × 0.3–0.8 mm, subinsititious, probably terete when fresh, more or less equal, somewhat compressed in drying, cartilaginous, now “pinkish buff” 6A3 upward, somewhat duller downward, vestured from throughout to upward and downward but missing from midsection (probably through handling); vesture upward scattered and curly, downward becoming delicately strigose or hairy, near “tilleul buff” 7B2. Rhizomorphs not observed. Odor and taste not recorded.

Figure 86. 

Mycetinis yunnanensis. Basidiomata. ATFB 3103 BTFB 3145 C Arrangement of lamellae and lamellulae D Basidiomata. Standard bars: A, B, D = 10 mm. C = not to scale.

Known from three collections, all fruiting on fallen sclerophyllous leaves; so far known only from Yunnan Province, China; mid-summer.

Pileipellis near pileus margin (Fig. 87B) a tangle of coarsely diverticulate hyphae; hyphae 3–5 µm diam, thin- to firm-walled, obscurely clamped, often sinuous, with lobe-like diverticula often arising unilaterally; diverticula 3–6 × 2.5–4 µm, rounded, often dichotomous, occasionally capitate. Pileipellis over disc (Fig. 87A) composed of the following: 1) pileal hairs common, probably erect, -75 × 4.5–8 µm, thin- to firm-walled, often minutely roughened, usually subcapitulate; 2) a more or less monolayer of inflated hyphal termini ranging from subcapitulate to sphaeropedunculate (-25 µm diam), often lobed to free-form, often stalked (stalk -14 × 3–4.5 µm, obscurely clamped), thin- to firm-walled; rare thick-walled (wall -1.5 µm thick) individuals observed, usually strongly pigmented; 3) subpellis largely a repent layer of cylindrical hyphae (Fig. 88) 3.5–8 µm diam, thin-walled, inconspicuously clamped, often lightly encrusted with suggestion of delicate annular configuration; diverticulate hyphae of pileus margin rare to absent. Pileus and lamellar tramae loosely interwoven, free (not involved in slime matrix); hyphae 3–6.5(-8.5) µm diam, thin-walled, conspicuously clamped. Hymenium involving some vaguely slimy matrix, obscuring observation and illustration of structure bases and walls. Pleurocystidia (Figs 89, 91A) common, 16–25 × 6–8 µm, fusiform to swollen-fusiform, rounded at apex, inconspicuously clamped, thin- to firm-walled; contents more or less homogeneous, often vaguely partitioned. Basidioles subampulliform, becoming clavate; basidia (Fig. 91B) 20–23 × 9–11 µm, clavate, 4-sterigmate, obscurely clamped; sterigmata slender, curved. Basidiospores (Fig. 91E) 6–7.5(-8.5) × 3–4(-4.5)µm (Q = 1.67–2.33; Q^m 1.95; L^m = 6.9 µm), ellipsoid, subamygdaliform, gymnopoid (not tapering proximally), flattened adaxially, often somewhat humped abaxially, thin-walled, inamyloid. Cheilocystidia (Figs 90, 91C) (15-) 18–36(-45) × 9–20 µm, stalked [stalk 5–16(-25) × 3–4(-6) µm, clamped, thin-walled], lumpy or subarbuscular, coarsely diverticulate; diverticula coarse, 3–8 × 2–3.5(-7) µm, knobby to inflated into strangulate dichotomous lobes or clusters of broadly ellipsoid to subglobose cells often capitate, thin-walled, often terminating in pseudosterigma or beak. Stipe medullary hyphae 5–7.5 µm diam, firm- to thick-walled (wall -1 µm thick, hyaline), conspicuously clamped, free (not involved in slime matrix), parallel. Stipe cortical hyphae similar, producing caulocystidia as side branches or termini. Caulocystidia (Fig. 91D) thickly gregarious but not coherent, -120 × 5–7 µm, serpentine, occasionally internally septate, commonly branched (branches often lobe-like), thick-walled (wall -1.5 µm thick, hyaline), usually narrowed at origin, appearing delicately wooly (at 40×).

Figure 87. 

Mycetinis yunnanensis. Pileipellis structures. A Pileipellis structures of pileus disc B Diverticulate hyphae of pilus margin. Standard bars = 10 µm. TFB 3103 (TENBN-F-49172).

Figure 88. 

Mycetinis yunnanensis. Pileipellis hyphae. A, C Hyphae seen in profile; note ornamentation appears vague, perhaps spotty B, D Hyphae seen in upper wall surface; note suggestion of annular or striped configuration. Standard bars = 10 µm. TFB 3146 (TENN-F-49385).

Figure 89. 

Mycetinis yunnanensis. Pleurocystidia. Note vague content partitioning in A–D, G,H. Note clamp connections in B, E, G. Standard bars = 10 µm. TFB 3146 (TENN-F- 49385).

Figure 90. 

Mycetinis yunnanensis. Cheilocystidia. A-C, G, H Dichotomously lobate individuals D–F Multilobate individuals. Note beaked or pseudosterigmate apices in B, D, F–H. Standard bars = 10 µm. TFB 3145 (TENN-F- 49384).

Figure 91. 

Mycetinis yunnanensis. Microstructures. A Pleurocystidia B Basidia C Cheilocystidia DCaulocystidiaE Basidiospores. Standard bars: A–D = 10 µm. E = 5 µm. TFB 3103 (TENN-F-49172).

Macroscopically, basidiomata of M. yunnanensis closely resemble those of My. olidus from eastern North America. Experience indicates that these distributions are allopatric, and My. yunnanensis differs from My olidus in habitat (sclerophyll leaves for My. yunnanensis, less sclerotic deciduous leaves for My. olidus), cheilocystidia (cheilocystidia of My. olidus expanded, utriform or utriform-lobed), caulocystidia (setoiud, straight in My. olidus) and spores (11–16 × 3.5–4 µm; L^m = 13.7 µm for My. olidus). Similarity is merely superficial based on basidiomatal size and stature.

The transition of pileipellis from a tangle of diverticulate hyphae at pileus margin to a coarse hymeniform layer of expanded hyphal termini is gradual but dramatic. It parallels the same phenomenon in My. opacus, but otherwise, the two are quite different.

Basidiospores are easily collapsed, quite like those of My. olidus, but somewhat shorter. As several other Mycetinis taxa, large numbers of basidiospores remain lodged on or in the hymenium and are present when microscope mounts are made. Care must be taken, however, for most spores are semi-collapsed and not fit for spore statistics.

Unfortunately, taste and odor of fresh specimens were not recorded. An odor of garlic might be expected, based on its commonality in Mycetinis and particularly in M. olidus.

China, Yunnan Prov., Simao Pref., vic. Simao, “Red Flag Preserve,” N22°47'23", E100°58'33", 4.VIII.1990, coll. RHP, Wu Qiu-xin, Li, TFB3103a (TENN-F-49172; holotype); Yunnan Prov., Jinhong Pref., Xishuangbanna, vic. Menghai, N21°58'15", E100°27'09", nature preserve, 8.VIII.1990, coll. RHP, Wu Qiu-Xin, Li, TFB 3146 (TENN-F-49385); Yunnan Prov., Jinhong Pref., Xishuangbanna, vic. Menghai, N21°58'15", E100°27'09", nature preserve, 8.VIII.1990, coll. RHP, Wu Qiu-Xin, Li, TFB 3145 (TENN-F-49384).

In spite of an extensive literature (Singer 1955, 1959, 1965, 1969, 1973, 1975), two questionable illustrations (Singer 1973, fig. 96; Singer 1959 Pl. 1, fig. 1) and Singer’s report on the type specimen (Singer 1955), the affiliation of this organism remains in doubt. Some literature is arcane and/or imprecise and authentic herbarium material unavailable. Two detailed but almost identical descriptions (including but not limited to authentic and type specimens; Singer 1955, 1959) can be dissected, but Singer (1959, 1965) indicated a wide variation in macromorphological appearance (referring to four “forms,” although without formally proposing them).

Two characters give cause to consider the fungus as belonging in Mycetinis: 1) [Singer 1969: “The carpophores as well as the mycelium have a strong smell of garlic (which, in our region, they have in common only with Marasmius aporpohyphes), so that it is often smelled before it is seen”]; and 2) structure of pileipellis, described and illustrated as composed of swollen hyphal termini, often with diverticula plus diverticulate broom cell-like termini, all in an “epicutis of pileus with a distinct Ramealis-structure” (Singer 1955).

If eventually found to belong in Mycetinis, Ma. alliodorus would join the group of species with diminutive basidiomata, My. yunnanensis, My. olidus, My. cinnamomeus, etc.

Bullach’s (2003) report of Ma. alliodorus from eastern Russia is doubtful, equally so with reference to My. yunnanensis, known only from the other end of China. Another species of Mycetinis is to be expected.

Based on Singer’s protologue, illustration and reference (Singer 1969: 73) there is a slight possibility that M. aporpohyphes Singer could also be a Mycetinis. If so, it would be the only clampless taxon in the genus.

Marasmius epidryas is excluded from Mycetinis taxonomically by its phylogenetic placement in the Physalacriaceae. Ronkier and Ronikier (2011) showed a close relationship of M. epidryas to Rhizomarasmius pyrrhocephalus. Morphologically, microstructures had been accepted as similar to members of Mycetinis (Antonín & Noordeloos, 2008).

Nomenclaturally, Kühner's protologue did not include a Latin diagnosis, mandated shortly before the appearance of his publication. Ronikier (2009) explicitly validated M. epidryas.

Selection of a type specimen is also problematic. Antonín and Noordeloos (1993) considered that no type had been explicitly declared by Kühner “1935" (1936). Instead, they designated a neotype, “France, Haute-Savoie, Pralognan, 26.VIII.1968, R. Kühner (G).” As part of validation of the basionym, however, Ronikier (2009) designated a specimen with data agreeing with Kühner's original text (“En troupes denses sur les rochers, dans les trouffes de Dryas octopetala, an début de septembre, dans la région de Bozel, près de Moutiers-Salins (Savoie).” Ronikier's designation, however, was termed a holotype, a specimen which could only have been designated by Kühner, himself. Instead, Ronikier's selection must be considered a lectotype, this error being correctable under nomenclature rules.

Redhead et al. (1982) summarized literature on distribution of the species.